To use, substitute the outer tube of your first tubing section that connects to the stretcher head with the No. 404 Rapid Lock Channel Tube. Now, you are ready to stretch! To lengthen the stretch, pull the stretcher head forward until the inside tube spring clips drop into the desired slot. To shorten the stretch, lift the inside tube from its slot and move back to the desired position. Simple one-piece design with no parts to wear out. Adjustable in 2" increments with a maximum 16" adjustment. Constructed from 11 gauge steel which is almost twice the thickness of stretcher tubing. Black powder coat finish. Weighs about 2-1/2 lbs. and is 24-9/16" long.