Ding-dong Musical Melody Doorbell 12V Wired Door Bell For Access Control

Wired doorbell, buzz tone, soft voice loud and clear
Easy to install, 12V DC power supply, no battery installed.
Dimensions: Length 87 × 62 × 23MM
Color: White
Wiring methods:
Wiring (need 12V power supply use):
1, red with black 12V power supply positive and negative access terminal;
2, yellow with green signal line connected access control (BELL end);
Sound is: 80 db;
Note: This wired doorbell without the button can only be used with the door access control