FingerPop 12 LP Mailing Boxes, Box of 100 (LPBX100) by FingerPop All fold lines are perforated to produce sharp straight edges Made 12 1/2" by 12 1/2" to allow enough room for padding for 12" or 10" records Multi-depth with 2 perforated fold lines to allow for folding a 1/2" thick box or a 1" thick box Each box holds 1 to 4 albums Made from 200lb. test corrugated cardboard with 32lb. ECT (edge crush test)