Jiangsu Zhenya Special Screw Co.,Ltd is one of the leading China jam nuts manufacturers and suppliers,Website: , as a professional company, our productive factory is able to produce CE certification jam nuts at both high quality and low price. Welcome to buy discount and cheap, or wholesale products from us.Hex jam nuts are thinner than a standard hex nut but have the same dimension across the flats and corners. Hex jam nuts have two common applications:jam nut can be threaded onto a bolt and run tight against the standard nut which will lock the nut in place and prevent it from backing off. Jam nuts are sometimes used for leveling purposes as well.