selling it over on classifieds and was asked how it works. and i cant remember 🙂

ive used it, so it does work, but i cant remember what wheel, or what it actually screwed onto.
that internal thread looks to be about 34mm by the way. t'other side is just the normal cog and reverse thread locknut.

cheers

looks like an arai drag brake thread for a tandem rear wheel – same as the disk brake adapter I just got for mine. Or maybe it's for a screw on freewheel like the on-one SS hub I've got.

Can't see what it would screw on to other than a freewheel thread.

what size OD are freewheel threads?

That looks like it should be for pushing the chainline out if you are using a re-axled track hub in a roadie

sorted thanks. it screws onto a freewheel thread as cynic-al says.

cheers