I purchased this looking to mate it with one I already had from Index (still going strong). This though is a shoddy piece of copywork. Many many rough edges,unslippery clunking spring, the adjuster ring winds itself off. The hinge is a cheap rivet that fell out the first time I used it. Thinking I would fix it later, after running a marathon,skydiving and Baluga line fishing, I kept it. Yesterday I accidentally stood on it (very lightly). To my utter surprise the main portion of this totally instantly snapped in half. If I weighed half a ton and had jumped on it fair enough,but not the case.I am glad it broke on the floor and not pressed hard against my meagre forearm. the damage could have been pretty serious.