MADASTY

Description

Zero RF at the Ear and ELF Cord Shielding for Daily Listening

Every standard earbud — wired or wireless — places the speaker or Bluetooth transmitter at your ear canal, making your head the closest point to the EMF source. DefenderShield® Air Tube Earbuds change that by relocating the speakers to the bottom of the 7-inch hollow air tube routing sound to your ears. Only acoustic waves travel that final stretch — no electrical current, no electromagnetic field reaches your head or ear canal. 

The speakers sit at the bottom of the 7-inch air tube, physically separated from your head, with no Bluetooth transmitter, no battery, and no wireless signal near your ear at any point during use.

The braided nylon cord is infused with copper to reduce the Extremely Low Frequency (ELF) radiation that the audio signal wire would otherwise emit — the shielding step most wired and other airtube earbuds skip. 

Protected under Patent License #6453044. EMF shielding performance verified through FCC-accredited lab testing.

Clear Stereo Sound for On-the-Go Use

DefenderShield® Air Tube Earbuds are tuned for clear stereo sound across calls, music, and podcasts. The built-in microphone and inline controls let you adjust volume, play or pause audio, skip tracks, and answer calls without reaching for your phone.

Six ear tip sets are included for a precise fit: three sizes of silicone round tips for everyday use and three sizes of sport tips with in-ear hook for workouts and movement, plus two spring-loaded cord clips that attach to your collar to take the cord weight off your ears during a run. At 25.4 g — lighter than most sets of keys — the earphones go anywhere your phone goes. Add Memory Foam Ear Tips above for a more personalized and secure fit.

Available in 3.5mm for the widest compatibility and USB-C for newer supported devices, including iPhone 15 and newer, Google Pixel, and newer Samsung models.

 In EMF Academy’s 2026 roundup, DefenderShield was rated #1 Best Overall, with the reviewer praising the sound quality as “far better than any I’ve heard” among air tube options.

Features

How to Use

1.Choose the version that matches your device

3.5mm for the widest compatibility, or USB-C for newer supported laptops, tablets, and smartphones such as iPhone 15+, Samsung S20+, and newer Android models. If a device has both ports, the 3.5mm is more likely to support audio and microphone connections. Make sure the 3.5mm port is a TRRS / 4-pole port for full sound and mic functionality. For devices with a USB-C port, check device settings to ensure it is an audio and microphone-enabled analog USB-C port. Many are just charging ports or audio-output only.

If you have an iPhone 14 or older, choose the 3.5mm version and use a Lightning-to-3.5mm adapter that supports TRRS / 4-pole headset connections. Apple’s Headphone Jack Adapter works correctly. Many generic or TRS / 3-pole adapters support audio only, so the microphone and inline controls may not work.

2.Select your ear tip style and size: 

Make sure to test out the different sizes, small, medium, or large, of the various ear tip styles to find the perfect fit. Use the round silicone tips for everyday listening. Choose the memory foam ear tips to conform to your ear canal for a more comfortable or secure fit. Use the sport tips with in-ear hooks for a more secure fit or during activity. For workouts or walking, attach the two spring-loaded cord clips to your collar or shirt to help keep the cord secure and reduce pulling.

3.Insert the earbuds and enjoy clear, low-EMF sound

To insert the earbuds, gently lift the top of your ear and twist the earbud inward until it feels comfortably seated. The right earbud, the one with the microphone and controls, should be worn in the right ear.

Before listening, set your device volume low, below 65 dB, and raise it until you can hear comfortably.

For Maximum EMF Reduction

• Use inline controls to manage calls rather than picking up your phone — keeping the device away from your head, either out of reach or in a nearby shielded case in your pocket or bag during calls adds meaningful distance from your brain.
• During long listening sessions, rest the phone on a table or in a bag. The 42.5-inch cord provides adequate reach without holding the device.
• For the most complete protection during phone calls, use these earbuds for audio and pair your phone with our EMF-blocking case. Together, they help reduce exposure at both key points of contact during calls.

Care Instructions

• Wipe ear tips with a soft damp cloth or isopropyl alcohol wipe after workouts.
• Clean the cord with a dry microfiber cloth — do not submerge in liquid.
• Straighten air tubes gently if kinked or curved — air tubes may be curved when removing from their carrying case, but will straighten with time and by gently stretching. Store in the included hard carrying case when not in use, being careful to wrap air tubes gently so they don’t get kinked. Kinks reduce audio volume and clarity.

Specifications

Physical Specifications

EMF Protection Specifications

Compatibility — 3.5mm Version

Compatibility — USB-C Version

If you need replacement earbud tips, you can order them here.

Videos

Watch the full product demo — see how DefenderShield Air Tube Earbuds deliver sound through hollow air tubes, include a built-in mic and inline controls, and help eliminate near-ear RF exposure without Bluetooth.

Troubleshooting

If your earbuds aren’t working, often the earbuds are not defective but the device, port, or adapter you are using. Even if the port looks correct, it may not be compatible.

Follow the guide below to ensure your earbuds are functioning properly.

Our Top Tips:

• Adapters complicate compatibility. Direct connections are the most stable.

• If devices have multiple port options, the 3.5mm earbuds have the most universal audio and mic connection. 

• For devices with unsupported ports (regular USB, Lightning) it is better to use the 3.5mm earbuds with an adapter, than to use USB-C earbuds with an adapter.

• The earbuds should work on most devices (with the correct adapter if needed) for audio connections, while the mic and controls may be less universally compatible.

3.5mm Earbuds Information

Compatibility

Device port AND adapter (if used) needs to be a TRRS (4-pole) connection.

Our 3.5mm earbuds include a microphone, which requires a TRRS (4-pole) connection.

• TRRS (4-pole) → audio + mic + controls
• TRS (3-pole) → audio only (mic and controls will not work)
• Always use adapters labeled TRRS, 4-pole, or “supports headset/mic”.
  • Make sure there are 3 lines on the ring of the jack, otherwise, the microphone and controls may not work.
  • Cheap or generic adapters are often just for charging (audio and microphone/controls won’t work) or audio (microphone or controls won’t work).
  • Adapters that may not fully work:
    • Cheap “pass-through” adapters (no DAC)
    • Plane/dual-prong adapters
    • Splitters not rated for TRRS
    • Many Amazon Basics or generic adapters
    • Confirm your device supports TRRS (4-pole) 3.5mm jacks for audio and mic (input and output).
• Common devices with TRS-only jacks (may not fully work):
  • Desktops and some laptops
  • Older computers with separate headphone + mic jacks
    • Handheld gaming devices
    • Cameras with separate headphones + mic jacks
    • Any device that requires a USB-C or Lightning connection without an active, MFi/USB DAC adapter
  • Check device input/audio settings to select the external headset/mic.

  • Test the earbuds on a different device (or 2) to confirm they function.

  • Refer to your device manual or manufacturer website for “headset with mic” support.

How do I fix an unsupported adapter or port?

Devices with a TRS-only port cannot be changed to recognize and support mic input. Earbuds should work for audio, but without full mic/controls functionality.

You can purchase a 4-pole TRRS 3.5mm adapter, just make sure it says “supports headphone and mic”.

Typical Problems & Fixes:

Audio works but microphone doesn’t:

• Likely wrong adapter (TRS instead of TRRS) → use TRRS/4-pole adapter. It must include a DAC if adapting to USB-C or Lightning (cheap pass-through adapters won’t work).

• Device not selecting external mic → check audio/input settings.

• App may be blocking external mic → test in a native voice recorder app.

• Plug not fully seated → push until it clicks, remove case if blocking.

• Device port is audio-only → check device settings, or test the earbuds on a few different devices. If it works on other devices, the port likely only supports audio.

Inline controls (play/volume/skip) don’t work:

• Some devices ignore analog controls →  this is a device limitation — the earbuds themselves are fine.

• Adapter may not support inline signals → test in a device without an adapter and if it works, get an adapter that supports inline signals.

• Your device’s media volume may already be at maximum or minimum → check native device volume control.

• On some devices, the inline volume buttons control media volume, not call volume — try playing music or a video while adjusting.

• When using with music apps, some devices require the media app to be active first before the earbuds’ inline controls can send commands → Hit Play directly on the device. After the audio starts, the earbuds’ buttons should work as expected.

• The control buttons may be stuck or jammed → press each button a few times in different spots with varying pressure. Try a longer, firmer press and release. If it still doesn’t work, gently clean around the buttons with a dry brush/cotton swab to remove dust or debris.

Static, low volume, or one side cutting out:

• Straighten kinked air tubes.

• Clean debris from the port.

• Clean debris from the ear tip and make sure the ear tip is correctly placed on the earbud.

• Check Accessibility → Disable Mono Audio to restore normal stereo output.

• Reset EQ or audio effects.

• Re-seat the plug firmly and make sure a case isn’t getting in the way.

• Turn off Bluetooth to ensure audio isn’t being routed wirelessly.

• Adapter or device issue: Try using it in a different device that doesn’t need an adapter (it may be a faulty adapter connection). Or, try a different device WITH the adapter. If it exhibits the same problem, the adapter is the issue.

Ear tips fall off the earbuds:

Ear tips are designed to be interchangeable and may not have been put on correctly, or are not fully seated.

• Remove the ear tip, check for damage, then pinch ear tip and stretch it over the earbud stem as far as it can go, twisting as you place it on.

• The sport tips feature an in ear hook with an R or L→ Make sure you match the right sport tip (R) with the right earbud (side with  mic and controls). Stretch the sport tip on top of the earbud, fully covering the raised silver ring on the earbud attachment. Twist into place so that the ear hook extends directly up.

• Watch our ear tip replacement video on our website.

Ear tips fall out or don’t fit correctly:

Due to the high quality metal stereo speakers at the bottom of the air tubes, the earbuds have to hold more weight than a normal pair of earbuds, so they may feel less secure.

• Try out all sizes of ear tips (S, M, or L) to find the best fit in your ear.

• Our earbuds have a left and right side. Make sure the right earbud (with mic and controls) is in your right ear. Pull the top of your ear up and gently twist until the ear bud is firmly and comfortably seated in your ear. The slanted ear tip should be angled 35° forward towards the front of your face.

• The ergonomic sport tips come with an in-ear hook for an extra secure fit.

• Using the 2 plastic metal-sprung clips, clip each wire just below the air tubes to your collar or shirt to support the weight of the earbuds and reduce movement. Our earbuds are compatible with most third-party earbud tips and ear hooks, allowing you to purchase a custom option to provide the most comfortable and secure fit for you.

USB-C Earbuds Information

Make sure your device port supports analog USB-C audio (adapter not recommended).

There are different types of USB‑C headphones/adapters:

• Active:  Has its own internal DAC (digital to analog converter) + amp. It expects digital audio from the device.
  

• Passive / “Accessory Mode”: Relies on the device to output analog audio through USB‑C just like a 3.5 mm jack would.

Our USB-C Air Tube earbuds use analog audio signaling with a microphone, meaning it works with devices that support analog audio input. That means the device has a DAC to convert the audio from analog to digital.

Every device manufacturer handles analog USB‑C differently — some support it fully, some partially (audio yes, mic no), and some not at all. Apple does not explicitly state analog USB-C earbud compatibility with its newer USB-C iPhones, but our own testing has shown consistent functionality with the DefenderShield USB-C earbuds.

Key Note: Analog USB‑C headphones work best directly plugged into a device that supports analog USB‑C audio. Mic and inline controls may not function on partially compatible devices, or when using an adapter.

How to check compatibility:

Confirm your device supports analog USB-C audio/microphone.

• Likely compatible devices:

• Samsung Galaxy S20 and newer

• Newer iPad Pro / iPad Air with analog USB‑C audio

• Some Chromebooks or Windows laptops that support analog USB‑C audio

• iPhone 15 and newer (*doesn’t explicitly state analog USB-C support)

• Likely incompatible or partial function:

• Android phones with a 3.5mm and USB-C port (Moto G Stylus 5G) don’t support any USB-C audio

• Samsung Galaxy Z Fold

• Motorola Razr

• OnePlus Nord series

• Most Windows laptops without analog USB‑C audio

• Nintendo Switch (audio may work; mic may not)

• USB-C hubs, multi-port adapters, charging-only adapters, or extenders

• Test on another known compatible device to confirm functionality.

• Refer to your device manual or manufacturer website for “USB-C analog audio” or “headset with mic” support.

Adapters / Hubs:

• Plug directly into the device for the best results.

• Avoid multi-port USB-C hubs, charging-only adapters, docking stations, car USB ports, or USB-C extenders.

• Lightning to USB-C requires an adapter that is labeled "Charging and Audio" or "Data Transfer" to support full functionality.

How do I fix an unsupported adapter or port?

If the device has an audio and mic compatible port (3.5mm, Apple Lightning), purchase an adapter that converts to USB-C analog audio with microphone. Depending on the adapter, there may still be issues with mic and inline controls.

Devices that do not support analog USB-C with mic input cannot be changed to recognize the earbuds, and there is not an adapter that will convert USB-C analog audio earbuds to digital. Earbuds may be audio-only.

Typical Problems & Fixes

Audio works but microphone doesn’t:

• Device may not support analog USB-C mic → check audio/input settings.

• Android: Settings → Sound → Input → select “Headset Microphone”

• App may be blocking external mic → test in a native voice recorder app.

• Plug not fully seated → push until it clicks, remove case if blocking.

• Test on a different compatible device → if it works elsewhere, your device likely does not support analog USB-C mic input.

Inline controls (play/volume/skip) don’t work:

• Many devices only support digital USB-C commands, so analog controls may not function → this is a device limitation — the earbuds themselves are fine.
• Adapter may not support inline signals → test in a device without an adapter and if it works, get an adapter that supports inline signals if possible or try to use without an adapter.

• Your device’s media volume may already be at maximum or minimum → check native device volume control.

• On some devices, the inline volume buttons control media volume, not call volume — try playing music or a video while adjusting.

• When using with music apps, some devices require the media app to be active first before the earbuds’ inline controls can send commands → Hit Play directly on the device. After the audio starts, the earbuds’ buttons should work as expected.

• The control buttons may be stuck or jammed → press each button a few times in different spots with varying pressure. Try a longer, firmer press and release. If it still doesn’t work, gently clean around the buttons with a dry brush/cotton swab to remove dust or debris.

Static, low volume, or one side cutting out:

• Straighten kinked air tubes.

• Clean debris from the port.

• Clean debris from the ear tip and make sure the ear tip is correctly placed on the earbud.

• Check Accessibility → Disable Mono Audio to restore normal stereo output.

• Reset EQ or audio effects.

• Re-seat the plug firmly and make sure a case isn’t getting in the way.

• Turn off Bluetooth to ensure audio isn’t being routed wirelessly.

• Adapter or device issue: Try using it in a different device that doesn’t need an adapter (it may be a faulty adapter connection). Or, try a different device WITH the adapter. If it exhibits the same problem, the adapter is the issue.

Ear tips fall off the earbuds:

Ear tips are designed to be interchangeable and may not have been put on correctly, or are not fully seated.

• Remove the ear tip, check for damage, then pinch ear tip and stretch it over the earbud stem as far as it can go, twisting as you place it on.

• The sport tips feature an in ear hook with an R or L→ Make sure you match the right sport tip (R) with the right earbud (side with  mic and controls). Stretch the sport tip on top of the earbud, fully covering the raised silver ring on the earbud attachment. Twist into place so that the ear hook extends directly up.

• Watch our ear tip replacement video on our website.

Ear tips fall out or don’t fit correctly:

Due to the high quality metal stereo speakers at the bottom of the air tubes, the earbuds have to hold more weight than a normal pair of earbuds, so they may feel less secure.

• Try out all sizes of ear tips (S, M, or L) to find the best fit in your ear.

• Our earbuds have a left and right side. Make sure the right earbud (with mic and controls) is in your right ear. Pull the top of your ear up and gently twist until the ear bud is firmly and comfortably seated in your ear. The slanted ear tip should be angled 35° forward towards the front of your face.

• The ergonomic sport tips come with an in-ear hook for an extra secure fit.

• Using the 2 plastic metal-sprung clips, clip each wire just below the air tubes to your collar or shirt to support the weight of the earbuds and reduce movement. Our earbuds are compatible with most third-party earbud tips and ear hooks, allowing you to purchase a custom option to provide the most comfortable and secure fit for you.