Each spring features a back bend design at both ends, ensuring it stays securely in place. The machine-cut springs are uniform in size, providing stability with clean cuts that prevent rubbing or rusting. This sofa spring repair kit is intended to attach a zigzag curved, non-recessed spring to the wood frame of upholstered furniture for both seat and rear spring applications. Crafted from carbon steel and subjected to heat treatment, these springs exhibit excellent elasticity and toughness. The design includes a 48mm high arch position and 25mm short spacing, enhancing the supporting force with added material at the foot. Repair Sagging Cushions -- Our sofa spring repair kit includes all the components you need for constructing a new chair or restoring support to a sagging sofa. Save Money -- Why replace furniture when you can repair it at a minimal cost? We utilize these same springs in all commercial and custom furniture.