... selection.5) Easy instillation, no wiring needed, no labour involved. (wireless doorbell)6) Easy mobility, suitable for house, villa, office, ... than 100 meters8) Five colours can be chosen: Silver, blue, purple, green, yellow. 9) AA batteries is used in receiver. ... )QTY/20FTQTY/40FTB2-C1(C3)DC wireless doorbell57.5x31.5x356012.210.82550054900B2-C4DC wireless doorbell52.5x32.5x71.56017.815.11320028500 ...