This is a track cog from "Phil Wood", a company that has been producing high-quality parts in San Jose, California since 1971 that can be used with confidence for a lifetime.
The Phil cogs boast high precision and are polished to a mirror-like finish, ensuring excellent chain release.
SPEC
Number of teeth: 12T, 13T, 14T, 15T, 16T, 17T, 18T, 19T, 20T, 21T, 22T
Standard : 1/2 "x1/8" (thick tooth)
MADE IN USA