BUY WITH CONFIDENCE - Rest easy with a CIUANCE twin mattress. Every CIUANCE twin mattress is backed by a 100-Night NO-RISK Trial and 10-Year support. Please let us know if you experience any issues or are not satisfied with the product. DUE TO THE LONG-TERM OF VACUUMED COMPRESSION, SIZES MAY SUBJECT TO ±0.5 INCH. HYBRID DESIGN FOR ALL SLEEPERS - The CertiPUR-US certified memory foam and pocketed innerspring hybrid construction reaches a balance between comfort and support.The twin size mattress provides the targeted support to your body, proper back support & alignment. No worry about slipping off the bed. STAY COOL ALL NIGHT LONG - The twin bed mattresses are made of high-end knit fabric with a comfortable and breathable surface. A 1.5” layer of pressure relieving gel memory foam adapts to your unique body shape and size, while contouring to your curves. Multiple support layers ensure long-lasting comfort and no sagging. EDGE SUPPORT & MOTION ISOLATION - The high-quality carbon steel spring coil has high flexibility and provide excellent customized support for your skeletal system. They work independently from each other, effectively absorb sound and vibration, evenly distributed body weight. It also reinforces the edge support and isolates motion transfer to a significant extent. TWIN MATTRESS IN A BOX - twin sized mattress is compressed, rolled, and shipped in a box for ultimate convenient delivery. Shipping Dimensions of twin bed mattress : 43"L x 11"W x 11"H. For a better sleeping experience, please ALLOW 48-72 HOURS FOR THE MATTRESS TO FULLY EXPAND. mattress in a box