Warranty & Compatibility & Note: 12 months worry-free warranty; Compatible with All Speaker Mics with 3.5mm Listen Only Audio Jack; Compatible with Speaker Mic of Motorola Commountain Kenwood Baofeng Icom Harris and more; This is not Intrinsically Safe earpiece, Don't use it in hazardous areas; This is not water-proof earpiece, Don't use it under humid environment and rainy day. Professional Acoustic Tube Module: Super quality TPU acoustic tube provide durability and flexibility; Ear-hook and elastic coil made by precise forming technology makes your wearing more comfortable; Acoustic tube joints made of anti-cracking & wear-resistant plastic bring reliability and prevent scratching; High performance micro speaker and acoustic tube ensure sound to be transmitted clearly even in loud environment; A variety of accessories meet different ear wearing choice. Clear Sound Transmission: With professional acoustic tube module, high quality micro speaker, high purity co