Folding tail block is multi-function with three positions. Folding Tail block has a 20-inch flat position for stretching off straight walls. It folds square for stretching off outside corners found in "L"-shaped living room / dining rooms. You can stretch off round posts by putting the legs at a 135° angle. This also locks the pivot so you can stretch all the way around a post as can be helpful in basements. This tail block also has wheels to help move it down the wall fast, and solid rubber pads that help it stay put under load. Works with all Crain stretchers, as well as other stretchers with standard poles.