Today LAN71 tube mitre cutters (photo) are manufactured from PM T-15 powder metallurgy high speed steel supplied by the world's finest steel mills. Typical chemical composition is 1.6% carbon, 4% chromium, 12.25% tungsten 4.9% vanadium and 5% cobalt and typical hardness is Rockwell C 66. A high volume of hard vanadium carbides provides very high wear resistance. The cobalt content provides excellent cutting edge strength at high service temperatures which is known as "red hardness". Through the 1970's up until the late 1990's, LAN71 cutters were ground from M2 HSS. Beginning around 2007 M42 high cobalt material was used and then in 2009 we switched to PM T-15 powder/particle metallurgy. Powder metallurgy involves compacting millions of fine particles of steel which are even in size and uniform in carbide distribution into a bar of tool steel. For the finest tube mitre cutters available today, all LAN71 cutters are turned and ground from PM T-15 for its superior wear resistance, red hardness, toughness and grindability. While the cost of particle metal PM T-15 is greater than M2 and M42 cobalt high speed steel, the enhanced metallurgical characteristics greatly aid in machining the modern air hardening heat treated steel bicycle tubing.