Seat tube sizing gauge

Gauges based on Stein's very expensive sizing gauges (about $100 for the pair).

Used to measure the inner diameter of your bicycle's seat tube to determine your seat post size.

Obviously accuracy depends on material shrinkage, etc. Probably should run a test print.

These are hollow to save material. Little more than 5 mm wall thickness throughout.

Debossed the diameters in 1 mm. Each segment is 30 mm long. Last segment is 50 mm long, & has an axially centered hole to help extract it