Frame kit or receiver only: which Polymer80 listing to buy

Two listings, similar names, very different orders. Here is how to tell which one you need.

What a kit includes

The unfinished frame or receiver, its steel rail modules where applicable, the matching jig, the drill bits and the end mill. Everything the cutting stage needs. You still supply a drill, a vise and a file.

What receiver only includes

The unfinished frame or receiver, and for pistol frames the rail modules. No jig, no bits, no end mill. Cheaper by the cost of the tooling.

The rule

Buy the kit for your first build of a given family. Buy receiver only for the second and later builds of that same family, because the jig is reusable and does not wear out at hobby volumes.

Jigs are family specific

A PF940C jig does not finish a PF940v2, and the RL556v3 jig does not finish a G150. If you change families, you need that family jig, which means a kit again.

Multi-packs

The G150 lower is sold in 2, 3 and 5-packs with no jig. Pair one kit with one pack and the per-receiver cost drops sharply, which is the cheapest route to several rifle builds.

Bits wear before jigs do

The end mill dulls after several receivers. Keep it oiled, clear chips often, and buy a spare before the fourth build rather than during it.

This is general information, not legal advice. Laws on unfinished frames and receivers vary by state and city and change often. Check the current law where you live before ordering.