Working lock downs for years, and having to hook up and release all day long, this key always breaks. Anytime your cuffs get pulled, the dang thing breaks in the center. I always grind down the blade, but I do that with all my keys so they can double as a box cutter. I bought two. One lasted a whole three months, the first broke in 8 days. Go all metal. Evey time. Who cares how much a cuff key weighs? I sure don't. I am glad a partner told me about this site, for good old aluminum. My last aluminum lasted six years.