This door phone system allows you to talk to visitors before opening the door. There is also an additional function to allow the opening of an electronic lock. Ideal for use in domestic and business applications and helpful for the elderly or less mobile.Power supply[tab]12Vac, 1000mA[br]Dimensions (outdoor unit)[tab]160 x 113 x 68mm[br]Dimensions (indoor unit)[tab]210 x 85 x 60mm[br]Weight (outdoor unit)[tab]350g[br]Weight (indoor unit)[tab]340g