17/32" Reduced Shank Drill Bit
It's a drill bit.
Are you still reading? Okay I guess I'll give you a little more information. It's a 17/32" Drill Bit used for drilling holes to install 5/16" nutserts (you know those things everyone hates installing?). Well if you use this little gem it reduces the the cussing of accidentally enlarging the hole to big and messing everything up!