Plug-in Chime for Wireless Video Doorbell Entry Chime with Adjustable Volume Music Selection Ding-Dong Door Bell Chime 433MHz Frequency (AC 90~250V) The plug-in chime will be activated when a visitor is pressing the smart doorbell. Plug-in chime is a practical tool that matches with smart doorbell, and they both provide home for you! Plug-in Chime for Wireless Video Doorbell Entry Chime with Adjustable Volume Music Selection Ding-Dong Door Bell Chime 433MHz Frequency (AC 90~250V): 433MHz frequency, compatible with wireless video doorbell.Plug-in chime, easy to use, designed for indoor use only.Different melodies for selection, meeting various needs.A chime can pair with multiple doorbells, a doorbell can pair with multiple chimes.Adjustable , low to mute, to 110dB. Note: Size and color may be slightly different due to manual measurement and different light conditons or other reasons, please in kind prevail. Thanks for understanding. Specifications: Music Selection: Support Package Weight: 100g / 3.5oz Plug: US Material: Plastic Frequency: 433MHz Color: Black/ White (Optional) Volume: adjustable, to 110dB Power Consumption: 10mW Chime Size (plug not included): 82 * 82 * 20mm / 3.2 * 3.2 * 0.8in Voltage: AC 90~250V Package Size: 9.5 * 9.5 * 7cm / 3.7 * 3.7 * 2.8in Package List: 1 * User Manual (English) 1 * Plug-in Chime A chime can pair with multiple doorbells, a doorbell can pair with multiple chimes. Plug-in chime, easy to use, designed for indoor use only. 433MHz frequency, compatible with wireless video doorbell. Different melodies for selection, meeting various needs. Adjustable volume, low to mute, up to 110dB.