Zentrierring

The fit is spot-on for both the airframe and coupler tubes since they're machined to those two distinct inner diameters. I double-checked the CCR against my coupler and it slid in with just the right amount of friction, no shimming needed.

The labeling system between the CR and CCR rings is spot on, so I didn't have to guess which one went into the coupler tube versus the airframe. Everything seated flush with no sanding needed, which saved me a good chunk of build time.

The descriptions made it dead simple to figure out which ring goes in the airframe versus the coupler, so there was zero guesswork during assembly. They seated snugly with a satisfying fit right out of the package, and the build feels solid enough that I'm confident about the alignment on the next f