Wireless Doorbell

Sadotech wireless doorbell - used for about a year (resulting in the yellowing of the transmitter) but still works great. Not looking for much.

Bought from Amazon: https://www.amazon.ca/SadoTech-Wireless-Doorbell-Operating-Batteries/dp/B00FR4YQYK/ref=mp_s_a_1_14?adgrpid=57896063741&gclid=CjwKCAjwnrjrBRAMEiwAXsCc4-F-j___js-nngrJAAPnt98zozHcUqL5DTQbDC0USaLX2bBkqSy7hBoC-DQQAvD_BwE&hvadid=309996546138&hvdev=m&hvlocphy=1002376&hvnetw=g&hvpos=1t1&hvqmt=b&hvrand=13575790761661053224&hvtargid=kwd-25000790&hydadcr=28127_10626341&keywords=wireless+door+chimes&qid=1567531028&s=gateway&sr=8-14