-Consists of a sofa bed and a rolling trundle for more sleeping space-Trundle with 4 lockable rubber casters for stable and safe fixation-Not only as a cozy daybed with trundle but also a comfy sofa as a whole-Medium carbon steel for perfect sturdiness and rust resistance-Headboard and footboard made of MDF for better durability-Applicable to living room kid's bedroom dormitory and more-Platform design requires no box spring-Suitable twin size of mattress is 39" x 75" (L x W)-The recommended thickness of mattress is lower than 8"-Easy-to-understand manual to help you finish the installationSpecificationsColor - BlackMaterial - Medium carbon steel, MDF, rubberSize of Sofa Bed - 78" x 40" x 31"/ (L x W x H)Size of Trundle - 70" x 39" (L x W)Sofa Bed's Height Above The Floor - 14"Trundle's Height Above The Floor - 3"Load Capacity of Sofa Bed - 550lbsLoad Capacity of Trundle - 330lbs/