【Full-length elastic band】 accommodates all mattress sizes. The band can be extended to 316" in length to fit around a standard California King mattress. 【Hook & Loop fasteners】allow to tighten the bed sheet as desired & needed. The fastener can be attached and secured to the band at any point. 【Band width】at 3.94" =100mm ensures a heavy duty scrunching of the sheet to the mattress's perimeter. A silk sheet may impair the performance. 【No more worries】about picking up the wrong size. ✧ The hook & loop fastener with stretchable band keeps the sheets fitted in place and prevents sliding for all mattress from twin, full, queen, to king size. ✧ Re-attaching the hook & loop fastener will allow you to easily change the tightening strength. Stretch without fear! Now with increased band length for a comfortable and secure fit. We are listening. A heavy duty band works as 360-degree bed sheet holder and it keeps the sheet strapped firmly & tightly on the mattress. An adjustable bed band hugs the whole sheet to the mattress, not only the corners. It’s also a bed sheet tightener can be adjusted the tightening strength as to your wish.