Stem mounts clamp to 10-12 mm round mirror stems for a compact, sturdy and versatile mount. These blind-spot mirrors attached where you need them to keep scan distance minimal. There are two versions available of our motorcycle mirror clamp. The short OEM mirror stem version is made for cruiser style mirrors. Here the short mounting space requires the mirror housing to be mounted off to the side while the long stem are made for standard length mirror stems. Aluminum clamps use stainless fasteners and aircraft locking nuts for a quick and secure attachment. Money back guarantee. Note: A quantity of 1 = a left/right pair.