I have a mystery frame which is very similar to a boss....maybe it's an early one I really don't know!
Take a peek....
Picked this up at a bootfair a few years back... Thought I'd try and solve the mystery by just getting lucky on Google but no...I'll be stabbing in the dark for ages 😆 It's a 1 1/4" headset...which kinda dates it I'd imagine around v late eighties or early nineties... absolutely no other clues...
www.retrobike.co.uk
I was hoping to identify it before outing it just to satisfy my curiosity!