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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want a two-way radio earpiece that keeps private, hands-free communication going through a full work shift, choose Retevis RT22; if you need wired in-ear monitors built to make music sound big and detailed, choose erjigo KZ x HBB.
• Retevis RT22 — biggest strength: purpose-built for radio talk, with a rotatable mushroom earplug, a face-up PTT button and a claimed 10 hours of use. Biggest trade-off: it is a mono earpiece with no noise control, so it is a communication tool, not a music product.
• erjigo KZ x HBB — biggest strength: a three-driver hybrid setup (one 10mm dual-magnetic driver plus two 6mm drivers) with a wide 20 Hz–40 kHz range and a detachable silver-plated cable. Biggest trade-off: it is wired, has no radio PTT function, and its active noise cancellation is a very different feature from radio privacy.
• Pick Retevis RT22 if you work or play with a compatible two-way radio and need clear, private voice in noisy places.
• Pick erjigo KZ x HBB if you listen to music on a phone, laptop or player and want a bass-forward, replaceable-cable IEM.
• They barely compete. One is a radio accessory; the other is a music earphone. Your device decides this before sound quality does.
The Retevis RT22 (model EEK007, FC9158A) is a single in-ear earpiece with a microphone on a K-head 2-pin connector. The point of it is simple: it lets you talk and listen on a two-way radio without holding the radio. Instead of a handheld mic, you get a small earhook unit with a push-to-talk button on the cable, so your radio can stay clipped to a belt or vest while your hands stay free. That is the whole design philosophy, and it is a good one for anyone who is already carrying a radio all day.
The compatibility list is the real selling point. The 3.5mm/2.5mm K-head plug fits a long list of Retevis models — RT22, RT21, RT68, RT68H, H777, H777H, RT27, RT86, RT86A, RT86S and many more — and Retevis also lists Pxton, Baofeng (including BF-888S and BF-T26) and Kenwood radios. If you own one of those, this plugs in and works. The earplug itself rotates, so you can wear it on the left or right ear, and the mushroom tip is shaped to sit in the ear rather than hang off it.
The details are aimed at shift work. The PTT button faces upward for one-touch calling, the microphone is described as sensitive enough to stay clear in noisy settings, and there is a movable clip that doubles as a way to coil the cable so it does not snag. Retevis lists a 1.06-ounce weight, 16-ohm impedance, a 300 Hz–3400 Hz voice-focused frequency range, a 10-hour average battery life and a 1-year accessory warranty with a 30-day return window.
Who should buy it: security staff, event crew, restaurant and hotel teams, warehouse and manufacturing workers, airfield and casino staff, and anyone hunting, paintballing or running a convention floor with a radio in hand. Who should skip it: anyone who wants to listen to music. There is no noise control here, it is a single earpiece, and the frequency range is tuned for speech, not bass.
The erjigo KZ x HBB (KZ x HBB DQ6S) is a wired in-ear monitor built around three dynamic drivers: a 10mm dual-magnetic-circuit driver with a PET diamond molecular diaphragm, plus two 6mm drivers handling the high frequencies. KZ describes a physical frequency crossover and claims the dual-magnetic design improves electro-acoustic conversion efficiency by around 80%, which in plain terms is meant to give you more output and a wider response from the same input. The rated range is 20 Hz to 40 kHz at 25 ohms and 116 dB sensitivity.
What that buys you in practice is a bass-led, energetic tuning. The 10mm driver is the low-frequency engine, so sub-bass and mid-bass are pushed forward, while the two 6mm units are meant to keep the treble from sounding dull. KZ calls it a balanced three-frequency design; I read it as a fun, punchy sound rather than a flat studio reference, and the description that it was tuned by a professional tuner is the brand's claim, not a measurement.
The build is the other half of the story. The shell is clear resin, so you can see the drivers inside, with an alloy metal faceplate for daily wear. The cable is detachable silver-plated oxygen-free copper on a 0.75mm two-pin connection, rated for more than 10,000 plug-in cycles, and yes — you can swap it for a Bluetooth adapter (sold separately) if you want to cut the cord. There is a 3.5mm plug, a 120cm cable, an earhook-style wearing mode, and this version includes an inline mic and media controls.
Who should buy it: anyone who wants wired, bass-forward in-ears for a phone, laptop, DAC or player and likes the idea of a replaceable cable. Who should skip it: radio users. There is no push-to-talk, no radio connector, and it is not a communication accessory — it is a music earphone.
Side-by-Side: Which Should You Choose?
• Best for music listening → erjigo KZ x HBB. Three drivers, a 20 Hz–40 kHz range and a replaceable cable are all music features.
• Best for private, hands-free voice in noisy workplaces → Retevis RT22. The rotatable in-ear tip and sensitive mic are designed exactly for that.
• Best for wired sound quality on a phone or laptop → erjigo KZ x HBB. A detachable silver-plated OFC cable and a 3.5mm plug make it a straightforward everyday IEM.
• Best for long shifts on one charge → Retevis RT22. Retevis rates the earpiece at roughly 10 hours of average use.
• Best for upgradability → erjigo KZ x HBB. The two-pin socket lets you swap cables, and a wireless adapter can turn it into a Bluetooth set.
• Best for durability where it counts → both, differently. The RT22 leans on a firm clip and coiled cable; the KZ leans on a resin shell with a metal faceplate and a cable rated for 10,000+ insertions.
• Best for a single purchase that covers both jobs → neither. If you need radio talk and music, these are two different tools, not one compromise.
In my opinion, the smarter buy is the one that matches the device you already own. If you carry a Retevis, Baofeng, Pxton or Kenwood radio at work, I would buy the Retevis RT22: it is purpose-built for private, hands-free voice, it fits a huge list of radios, and it is rated for a full working day. If your priority is sound, I would buy the erjigo KZ x HBB — three drivers, a wide frequency range and a cable you can replace make it the better long-term audio purchase. If you are torn, be honest about which one you will actually plug in tomorrow.
FAQ
No. It uses a standard 3.5mm headphone plug and a two-pin 0.75mm detachable cable, not the K-head 2-pin radio connector the RT22 uses. They are not interchangeable for radio use.
They handle noise in totally different ways. The RT22 uses a well-seated mushroom earplug plus a sensitive mic so you can hear and be heard on a radio in loud places, with no active noise control. The KZ x HBB lists active noise cancellation and a sealed in-ear fit for music. Neither claim replaces a proper earplug for industrial noise.
Value depends on your use, not the spec sheet. If you need hands-free radio talk, the RT22 is the tool that does a job the KZ simply cannot. If you need music, the KZ gives you three drivers and a replaceable cable. Check the current price on Amazon for each and judge them against the job you actually have.
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