It is easy to install this invisible non-mortise barrel hinge used for wood panels 3/4" thick. Just drill the proper size hole and tap the hinge in flush. Secure mounting in the wood door or panel is assured by tightening the tensioning screw to expand the body of the hinge tightly in the hole. The solid brass hinge has a brass plated steel linkage and a 180º opening. It requires a 14mm mounting hole. Sold individually.