Scored this off of that well known auction site, only bid...........result.
A six inch conical hub from the 73/74 TR5T Adventurer, and B50 MX, it's a natural really matches the yokes and it's still Meriden. Odd that it's forty years old, only 20 years newer than the rigid frame yet it will still be damned as modern shit.
The pictures don't really show how compact it is.
3.711 kilos, which I reckon is around 8lb 2oz, is pretty light for a complete assembly I'd a thought. Haven't got a standard single sided hub set up to compare it against but a saving of 5lb can't be too optimistic.