Ice Hardened blades are cryogenically treated to minimize soft metal (austenite) and create more hard metal (martensite). The result is a metal cutting blade that is more consistently hard throughout, for up to 50% longer life than standard blades. A unique combination of relief angles forms a radius on the back of the tooth that reduces stress build-up during cutting and substantially extends blade life. Precision forming process creates sharper teeth for fast cutting. Matrix II bi-metal teeth for greater durability