DECT. 120 channels. Portable parent unit. Range 50 metres indoor/300 metres outdoor. Out of range indicator. Volume control. Sound sensitive light display. Music. 1 sing song and 19 melodies. Parent unit requires 2 x AAA batteries (included). Baby unit requires 4 x AA alkaline batteries (not included). Mains adaptor provided for both units. 1 parent unit. Manufacturer's 2 year guarantee.