Yellow Label Fretsaw Blades - Fine, Medium, Heavy & Extra Heavy. Available in packs of either one dozen (12) or one gross (144). Strong, sharp and long lasting. 130mm (5\") long to fit any handframe, treadle or power driven fret machine. For cutting wood, hardboard, plastics and most materials. Remember... the finer the grade, the tighter the curve. Please note: All blades are pin-less. Ref. TPI Use 00F 27 For fine overlay work. 0F 26 For fine overlay work. 1F 25 For 3mm (1/8\") wood. 2F 20 For 4.5mm (3/16\") wood. 3M 19 For 6mm (1/4\") wood. 4M 18 For 9mm (3/8\") wood. 5M 17 For 12mm (1/2\") wood. 6M 16 For 18mm (3/4\") wood. 7H 15 Multiple thicknesses. 9H 13 Multiple thicknesses. 10EH 12 Multiple thicknesses. 11EH 10 Multiple thicknesses.