This is one of those terribly useful aftermarket problem solvers that can save the day or wreck your frame, depending on how you attach it. To save the day, tighten it just enough so prevent slippage. It comes with a split lockwasher, but heck, man---add some blue threadlock to it, just to be sure.
To wreck your frame, overtighten it to the point where it starts to mash the chainstays, and then misinterpret the fact that the bolt keeps turning (as the chainstays keeps on flattening) as a sign that it's not tight enough, so keep on turning. You can use it on cheap or good bikes, but good bikes have thinner chainstays and while not at all delicate, they can still be wrecked, and that makes a sadder result. We still heartily endorse this, but use it mindfully. Don't just keep on turnin'...
Short bolt for kickstand plate and single leg kickstand users. Lucky you, your frame has a kickstand plate! Instead of hacksawing the regular kickstand bolt down to size get this stumpy 8mm allen for easy kickstand installation. BUT, cuidado! If you have a kickstand plate and a twin leg kickstand this short bolt is not strong enough a connection for the twin leg kickstand. Twin leg kickstand users need to use the sandwich hardware that comes with the twin leg kickstand - otherwise you won't have a kickstand plate on your frame anymore.