The Sargent Door Closer 351 is the most heavy duty closer made by Sargent. This closers meets ADA requirements, meets the Buy American Act, and is certified Grade 1, the heaviest rating possible. The closer has the capability to be mounted on the push, pull or top jamb, and is non handed. It ships with arm, plastic cover, parallel arm bracket and all of the fasteners. The hole spacing is 2-1/2" x 9".