The Walker Edison Twin Roll-Out Trundle Bed Frame offers a simple solution for additional sleeping space. The product is made with durable powder-coated metal for extra stability. The mattress slats of the bed are also made from the same material for extra support. Since the frame and slats are metal there s no box spring required for use. This black metal trundle bed frame fits standard Twin-size mattresses. There is no mattress included with the bed frame. The Walker Edison trundle bed has castors underneath to allow for it to easily roll in and out from underneath just about any style of bed. This feature makes the product an ideal space-saving solution. The extra sleeping area won t take up any additional space in your home when not in use. The Walker Edison Twin Roll-Out Trundle Bed Frame is ideal for guest rooms growing families and children s rooms for sleepovers and parties.