Location, temperature, and humidity will affect the airbed?s firmness. Airbeds will need to be occasionally re-inflated (topped off) to maintain desired firmness when used for more than a few days as vinyl tends to relax over time. * Measurements will vary based on customer?s inflation. Airbeds are measured from the widest point including the beams (bulges) on the side and off the tallest point from the floor including built-in pillows if applicable. * Twin-sized inflatable mattress with quality-tested 21.2-gauge waterproof flocked top * 15-gauge vinyl beams, sides, and bottoms for added stability while you sleep * Built-in, high-powered electric pump makes mattress easy to inflate and deflate * Customizable comfort level; 300-pound capacity; includes duffel bag for storage * Fits twin size fitted sheets; measures 80 x 19 x 40 inches (W x H x D); 90-day warranty * When using the airbed, do not turn dial to "deflate" setting as this will cause airbed to deflate immediately.