4Sleep vs Nature's Sleep Belize Gel Memory Foam vs Casper

4Sleep, Nature's Sleep Belize Gel Memory Foam and Casper are included in the same product category. You can buy these options in numerous sizes from Twin to Cali King. These models fit adjustable bed bases perfectly. Quilted foam is also a unique design featured in these trending sleep surfaces. These bed-in-a-box mattresses are easy to handle and unpack.