Before buying a HEST mattress we recommend measuring the width and length of your sleep space first to verify fit. Our mattresses are 100% memory foam and can squeeze into most spaces if they are slightly bigger. Even if a mattress is 3 - 5 inches too wide or long for your space, it most likely will still fit and be comfortable. For example if the wheel wells of your truck bed are in the way, the Dually will form around the wheel wells to fit the bed. Or if the mattress is too long for your truck bed, the extra couple inches can curl up to make an extra head rest/cushion. One of the nice things about memory foam is that folding/bending/or squishing the mattress won't affect its sleep performance.