Products : ? . : Designed by intensiveness fashion master to meet the market ; ? . : 4 levels adaptable from 25 dB to 100 dB ; ? . Inside : PCB board and IC parts are with well-set material, keeping yearlong lifetime ; Adopt whole number coding it is more permanent and can avoid interference ; ? . : Guarantee quality. Products first-class inside materials that keeps itself from getting higher temperature & interference ; ? . Practical : Easy installation, expedient, plug in socket and function normally ; with double-side stickers at the position of the removed button, also you can screws to fix it. . : All products passed CE, FCC, RoHS approval ; Range of application : House, office, hotel service, community building, factory, construction site and other than areas that is fit for short-distance radio receiver environments. It also can be best to present as its virgin design and overnice appearance, are very hot for household.Pairing and Change Ring TonePush button is freely match with receiver and vice versa.a -RRB- Select sought after ring tone by pressing Music Control Buttonb -RRB- Set Receiver into pairing mode by pressing the Volume Control Button on the receiver for about 5-7 seconds until LED flashes to get entered into `` pairing '' state. c -RRB- future, quickly or set the pairing process by pressing the transmitter button to pair with receiver. You will the tune you selected, which means that your operation is completed successfullyWhat 's in the package ? . 2 x Push Button -LRB- Transmitter -RRB- 3 x Plugin Chime -LRB- Receiver -RRB- 2 x Screws2 x Double-Sided Adhesive Tape2 x 12V Alkaline Battery1 x User ManualHere at physen, we you to make use of our Worry-Free Lifetime Warranty Guarantee.A laughing purchasing experience is the furthermost importance to us and we will happily send a product replacement if any issues arise.