M42 cobalt bi-metal cutting edge provides shock resistant teeth and resists tooth slippage 4/6 positive tooth configuration allows for fast, smooth cuts and less vibration 3/16-Inch back plate eliminates need for drive plate Package Dimensions: 8.128 L x 2.286 H x 5.08 W ...M42 cobalt bi-metal cutting edge provides shock resistant teeth and resists tooth slippage 4/6 positive tooth configuration allows for fast, smooth cuts and less vibration 3/16-Inch back plate eliminates need for drive plate Package Dimensions: 8.128 L x 2.286 H x 5.08 W (centimeters) Description M42 cobalt bi-metal cutting edge provides shock resistant teeth and resists tooth slippage. 4/6 positive tooth configuration allows for fast, smooth cuts and less vibration. 3/16-Inch back plate eliminates need for drive plate.