W/ sale and cloupon i got it for $28 so i couldnt pass it up. I have always heatd that you can use it to do kydex eyelets and to punch holes for sewing leather etc, but how does it work? Well, how it works is simple enough. What i dont understand is how ro add the sie sets or other things to the unit. All it is is a square endedwhen bar that cranks down on the disc with four gouges in it?