YCZ Wireless Doorbell Chime IP55 Waterproof Operating at Over 1000 Feet Range with 52 Kinds of Ring Tones. No Batteries Required for Receiver Premium quality; (Super long range wireless transmission, ultra strong penetration, signal stability, operating range up to 500 feet open areas). Transmitter with super rating IP44 waterproof, can be installed outdoor. The transparent compartment at the bottom of the transmitter allows visitors to leave message for you. 52 different ring tone for your selection; High quality and rotary acoustic fidelity, built-in stereo speakers with sound melody. Farewell to the invariable doorbell era, fashion pop, classic,make the ringtone vibe with your mood. The Series is a transmitter buttons, motion sensors and door sensors. Custom build your own system that fits for your needs. Easy to use pair-able random generated frequency code technology allows you to mix and match L Series components easily with one or multiple receivers. Easily plug receiver into an electrical outlet (no batteries required for main receiver).High quality for you to have one, as it is more sensitive, more stable, and power effective. You will hear the doorbell no matter how loudly inside, so you won't miss each visitor.