when you go into harbor freight, go to the 1st right hand aisle. now not the merchandise on the wall but on your left, the 1st aisle. they should be on a rack there. these are use by carpet layers. so maybe if you asked where the blades for carpet knives were they could direct you. good luck. and i have not had any bad experiences w/the blades cutting up my mat. and i've cut thru several layers of fabric just fine.