ZASHONT Heavy Duty 4-Inch Metal Box Spring Foundation with Fabric Cover - Powerful Support: Our 4 inch box springs for twin size bed engineered with heavy duty steel and reinforced internal structure prevents sagging and maintains boxspring integrity for years of reliable use - Twin Box Springs and Cover Set: ZASHONT Box springs twin size include a protective cover that shields against dust,and daily wear.Shrink and wrinkle resistant elastic band for healthier sleep surface - Anti-Squeak: Metal boxsprings twin size 4 inch features noise-free metal foundation,squeak resistant,providing a peaceful sleeping experience -Tool and Instruction: 4 inch twin foundation box spring come with tool and clear instructions for easily assembly