RVW1031 Features: * Matl. Thickness of 1-3/4", 1 each * Allen wrench after installation * Installation can be either inside the door itself or inside the door jamb * Ideally suited for all types of doors 1 3/8" thick or more * Closure rate is completely adjustable * Allow one spring closer for each 75 lbs * Does not require removal of the spring closer * Door weight for all spring closers * Recommended spacing is one half of the distance from the center of the door to the center of the top hinge