"Our T1 (AISI) steel offers 20% longer run times than M2-HSS. T1 is a well liked common European grade made of 18% Tungsten for extra long runs and better resistance to abrasive glue lines. T1 is the same hardness as M2 (63 Rc), making it easy to cut and profile grind. T1 is popular for mills that run mostly hardwoods or for softwood mills that want the ultimate in knife life and cutting performance. "