This is a Trimline cam lock made of high pressure, corrosive resistant diecast zinc. It features a baked-on-white enamel finish. A concealed locking mechanism pulls rails together helping to reduce air infiltration. The alignment lugs prevent side shift of the sash, and the slim-line design for narrow rail application With a lower profile it allows maximum sash opening. Mounting holes are 2-1/16 in. on center, with an 11/16 in. hole backset.