Introducing X-51™ bandsaw blades, featuring M51 tooth tips on a   fatigue-resistant blade backer, offering optimum performance cutting the toughest metals.  The combination of cobalt and tungsten at the tooth tip provides extreme heat resistance, which makes X-51 the right choice for cutting the toughest materials and large crosssections.  X-51 can take the heat that regular M42 blades just can’t stand up to.