Specifications?

Shank is for 1/4" (0.25) collet, which is the receiver on the router that holds the bit. This size shank is typical for light to medium duty use, say up to 2 h.p. rated router. Other variables need to be considered when comparing the size of the shank (collet) such as species of wood, bit profile, moisture content, etc. Generally, a 1/4" collet (shank) has wide utility for most applications.

1/4" shanks

Thank you for your question. The router bits for the 91030 set are 1/4" shank bits. These will fit all Skil 1/4" collet routers as well as other major brand 1/4" collet routers.