Summary

Base block for a hackle or set of wool combs. Add sharpened steel tines (polished nails or sharpened rod) to complete. Print with thick walls and an infill that'll take a load in any direction.

Alternatively, use as a blank to hold the tines for use in a stronger material by setting the margins and head height low.

Depending on material and thicknesses, heating the tines may make insertion easier and reduce cracking.

I don't have a reference object handy so defaults for the hackle are somewhat arbitrary.