"Bolts are used to hold the two housing parts of the coupling together. 

Made of stainless steel 316 with a round head and square neck, the bolts are corrosion free. If stainless steel nuts are used with stainless steel bolts, commercial anti-seize compound should be applied to the bolt threads

SUNSEED supplied nuts and bolts should be used for assembly of SUNSEED couplings to assure adequate tensile strength and correct fit.  Below are the maximum recommended torque ranges for fasteners."

Never exceed the recommended torque range. Provided the dimensions of the pipe and fittings grooves are correct, it is never necessary to tighten the fastener more than one-eighth turn after the bolt pad surfaces first contact. Incrementally tighten nuts on bolts to maintain a near equal gap between the bolt pads on each side. Under no circumstances should the bolt ever be distorted or bent by tightening the nut. If excessive force is required to establish bolt pad contact, disassemble the coupling and confirm that the groove dimensions in the pipe and fittings are compliant with specifications.