Pack of 20 - Replacement blade A for sharp accurate cutting with Logan Circle Cutter;For Foamwerks Circle Cutter by Logan Graphic Products Inc.;FOR USE ON STANDARD FOAMBOARD ONLY and not for cutting plexi, mats, hard plastic or for use on regular mat cutters;MUST USE FOAMBOARD UNDERLAYMENT WHILE CUTTING for a smooth clean cut and for proper blade maintenance;Convenient 20 pack of brand new blades for your circle cutter