Mainstays Bed Risers 4 Pack - Raises Bed 5.25 Inches Expands Storage Space Under the Bed 4 Pack raises each bed post 5.25 inches 1-inch lip to keep bed post or caster securely in place Limit per bed riser is 300 lbs / 136 kg Made of durable high impact resistant composite plastic polymer that is 100% Recycled Plastic