1. mainly used in the springs and frames connection for mattress, sofa,car seats . 2.factory direct 3.sell abroad welcome to see our web site We market the best price, selection of high quality materials to produce quality products, I hope there is a need for customers to contact us, and we can customize products to your specifications, I hope happy! sc-660 series Crown 16.8 mm High 8.7mmGauge 16 ...