These knives are V2 HSS with 63 Rockwell.  Dangerously sharp.  Great value.

Smooth Back, Bevel Edge - 6-1/16" Length x 5/8" Width x 1/8" Thick - Set of 3 Knives. Fits  Jet JJ-6. 

Why pay $80 for a set that is rated lower than ours.  Buy something else with your money like a dust collector or safety equipment.