Irwin Marples 4 Piece M373 Bevel Edge Chisel Split Proof Handle Set - MAR373S4N 4 Piece IRWIN Marples M373 Splitproof Bevel Edge Chisel Set. Contains the following sizes: 6mm (1/4in), 13mm (1/2in), 19mm (3/4in) and 25mm (1in). Metal striking cap allows use with a hammer, prolongs the life of the handle and prevents mushrooming. The soft touch handles are oil and water resistant to prevent slippage and to give improved comfort even during prolonged use. The handle design also reduces vibrations and reduces hand fatigue. One piece blade forging gives added strength and durability. Special tool steel ensures a much sharper cutting edge for quicker and easier operation. A special hardening process gives the blade a longer lasting edge - less time spent re-sharpening. The blade.