Operating range of over 300m(1000ft). Remote transmitter button is rated IP44 weatherproof. Easily plug receiver into an electrical outlet (no batteries required for main receiver). Blue lights flashing can help people with hearing impaired. 38 different ring tones. 4 levels of adjustable volume from 25db to 85db, Memory function for sound and chime selection. Push button can be fixed to the doorframe with screws, or attached using double-sided adhesive tapes. Package contents: TeckNet 1 Battery Operated Transmitter and 2 Plug-in Receiver. Free lifetime technical support and 18-month manufacturer's warranty. What's in box 1x Battery Operated Transmitter 2x Plug-in Receiver 1x Battery(CR2032) 1x Double-sided Adhesive Tape 1x User Manual.
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