As you can see, this bed can be contracted into a twin size bed or expanded into a large bed, it’s also with a trundle. This bed can accommodate 4 people to enjoy together. It's very convenient to share with your friends and relatives when they come to the house. It’s also a good choice for saving space. Description Material: Pine wood+MDF Size: Twin over twin/full/king Colour: White Numbers of slat (upper/down/trundle): 10/10/8 Function: Pull - out bed Decoration: With wheels Numbers of package: 2 Spring box: No need Assembly required: Yes Dimensions Upper Bed size: 40.4’’ x 79.5’’ Down bed (Normal/ stretch): 40.4’’ x 79.5’’/77.5’’ x 79.5’’ Total height: 59.8’’ Upper bed weight capability: 150lb Down bed weight capability: 200lb/ 400lb Trundle Weight capability: 200lb Upper bed recommended mattress thickness: 6’’ Down bed recommended mattress thickness: 8’’-10” Trundle Mattress thickness: 6’’