Retevis H-777 Walkie Talkies UHF Two Way Radio Long Range 16CH Flashlight Single Band 2 Way Radios(10 Pack) with Speaker Mic(10 Pack) Frequency range UHF;16 channel;rechargeable battery last 8-12 hours after full of the power Have been set to same when out of factory;could work together directly and easy to operate for your business Equipped with loud speaker mic and it will provide you hands free;also have the crystal voice transmission Built-in flashlight make things easier when in dark environment;it is the handy function for outdoor work We provide 1 year warranty and 30 days no reason to return; no matter any reason within 30 days you can apply for a return 360 Remote Clip Rugged Construction Durable PU Cord Crystal Nature Sound Sensitive Mic Handy Size Long-life