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. 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. Set includes: (4) 6" 14 TPI blades, (4) 6" 18 TPI blades, (2) 9" 10 TPI The Torch blades, (2) 9" 14 TPI The Torch blades, (2) 9" 18 TPI The Torch blades, and (1) storage pouch. No. 49-22-1131: Pieces In Set: 14 Pcs., Material: Bi-Metal, Application: Metal Cutting, Pkg Qty: 14, Package Type: Clamshell