How to identify OTK axle

I have an OTK chassis that my son races and loves, i bought it used and wanted to see which axle it has. I checked the usual spot where OTK label them and i cant find anything. Maybe been polished off at some point. Anyway, is there any other way to ID the axle? Wall thickness, internal colour etc?

Odds are it’s not an OTK and has been replaced. Check under the hubs and in the keyways for other markings.

Yeah i was thinking that could be the case as well. I’ll do some more digging and see what i can find.

I pulled the hubs and cleaned everything up really good and im starting to think its a Birel/freeline axle. The inside is spray painted yellow, i know freeline do that, and birel is everywhere in southern Ontario so it would make sense.

OTK’s only indicator as far as I know is the stamped letter on the left side of the axle. They don’t paint the inside of their axles. But that stamped letter does wear off over time.