52 Ring Tone LED Flashing Doorbell for the Deaf with 300 Working Range Description:1. Unique modern design, exquisite color box packing 2. High quality, approved by CE, FCC, RoHS,ISO9001 3. 52 high-quality melodies, 4-level adjustable volume 4. Over 200m operating distance,with LED flash light 5. Learning code, can work with different sensors..