[Professional Referee Intercom]: Using optimized Qualcomm Bluetooth 5.1 chip, EJEAS FBIM can achieve quick pairing and keep low-energy consumption. It supports 4 people real-time intercom and the talking distance can reach 1500m(distance of 4 units). | [CVC Noise Reduction Technology]: FBIM referee bluetooth intercom adopts advanced CVC noise reduction technology to eliminate the echo and ambient noise of the call, so that the sound you hear is more clear and stable, with 3D sound effect. | [Long Battery Life]: FBIM Bluetooth referee communication system runs on 850mAh high-capacity rechargeable battery. Just charging for 2.5h, the standby time is up to 260h and talk time can reach 19h, which can meet the needs of long-time referees communication. | [Wide Applications]: Professional referee FBIM is an excellent partner for most competition referees like football referees, basketball referees, golf referees, etc. In addition to referees, FBIM is suitable for daily training, construction sites, venue scheduling and other outdoor activities. | [Nifty Portable Design]: EJEAS FBIM is small and portable, easy to install and carry. With the in-ear headphone design, the wearing is more stable and secure. You can put the interphone into your armband, and it will not affect the intercom effect when moving fast.