Product Details:
Properties House-Service Detector Tester 
Type Heart Rate Monitor 
Model Number HRM-2800 
Feature wireless heart rate, pulse transmitter 
Material PU & ABS 
Transimitting distance 80cm -- 100cm 
Size 30.4(L) x 3.5(W) x 1.16(H)cm 
Imprint Size H. 10 x L.35 mm 
Weight 52.3g 
Color black 
Frequency 5.3k 
Battery Type Button cell CR2032 x 1pc 
warranty 1 year