Activate the childproof trap door with a simple turn of a knob. A button keeps the top closed with rubber seals in the lid to contain odors. Unit has a reusable cartridge which reduces waste and makes changing refills quick and easy. Made of ABS scratch resistant plastic. Refill bags hold 335 diapers each bag and are sold separately. Measures 13 1/2"W x 9 1/2"D x 21 1/2"H.