Strong triangular design for triple protection and a more permanent fixation. Works with almost all types of bedding. Set of 4 fitted sheet tighteners, original length is 9.5cm to 16cm, extendable to 25cm to 45cm, adjustable length allows you to achieve the desired tension. p> Designed to hold the cover securely in place and ensure a smooth, wrinkle-free surface for much better results. Suitable for bed sheets, ironing board covers, seat covers, sofa covers, mattresses, blankets, quilts, tablecloths, etc. Bed sheet or ironing cover will be held in place thanks to these 4 tighteners! Equipped with plastic-covered metal clips, they hold the sheet or ironing cover securely in place.