20TBC 1554-09 - 3” 20-tooth blocking comb – For trimming, blocking and carving.
From their website:
All of Oster® blades are put through a 12 step process guaranteeing quality and craftsmanship. We start with a fine-grain carbon steel that is heat treated to create a hard surface for greater wear resistance, leveraging a Rockwell Hardness Rating of 62. Our patented Cryogen-X™ process takes the blades down to a -300 degrees for a deep freeze, producing a harder, sharper blade which extends the product life. Each blade is then hand lapped for a smooth cut finish.
For trimming, blocking, and carving
For use on the 3" shearing head and professional hand pieces