when this was first made, the pin holes were of a completely arbitrary size- can't remember exactly, but bigger than 1/4". I don't even have a drill bit the right size so what the hell was I thinking? So I smashed a couple brass slugs into the holes and I'll be drilling the brass to fit standard corby bolts. I've sat on my ass with this knife for years, and I wish I'd thought of it sooner because it's 85% done. I made a mess with my grinder today, lots of mistakes to correct. But I'm a newb, so I try not to be too hard on myself and count all the f-ups as tuition