Weighted blankets get their weight from pockets of beads integrated into the fabric. The beads may be made of glass, plastic, or ceramic. Generally speaking, the blankets that use glass will be thinner than the plastic-beaded blankets of the same weight, because glass is a heavier material. Speaking of material, take note of what the cover is made of. Cotton and micro fibers will help keep things cool, while plush, minky material will be warming. Regardless, if your blanket doesn’t have a removable cover, we recommend you buy one with it, as most home washing machines can’t handle the weight.