5 Piece Chisel Pack for Arbortech Power Chisel includes a 20mm No. 3 gouge, 12mm No. 5 gouge, 13mm No. 9 gouge, 7mm No. 11 gouge, and 60 degree 8mm No. 12 gouge. As a safety precaution, the quick-change chisels are only active when pressed into the workpiece. Blades require honing before use.