Glield Extend 23" to 78"Adjustable 2-Piece Under Sofa, Mattress, Bed Sheet Fitted Fastener, Long Strap Clip Bands BDJ06 1. Set of 2 long straps with metal clips. 2. One size fits all stretchable elastic. (Fits oversized mattresses) 3. Adjustable from 23" to 78" (60cm to 200cm). 4. Under mattress "x" form installation. 5. Holds tightly in place, bed sheets, mattress pads, tablecloths, ironing board covers, slipcovers and more.