Cartridges Catalogue Numbering System How Do Catalogue Numbers Work? Each character in our catalogue number signifies a specific trait of that product. Use the following key columns and corresponding images to easily identify which attributes apply. MCFNR10CA3 M C F N R Insert Insert Shape Cartridge Insert Clearance Hand of Tool Clamping System Style Angle C Right-hand cartridge C F K C R D L J N Top clamping by clamping finger for inserts without hole. R Q R P M S S G Left-hand cartridge L T W Top and hole clamping for inserts with hole. P Insert clamping by toggle lever for insert hole. S Centre clamping by screw for inserts with hole. C88 widia.com