Trans ID help

I know I'm showing my ignorance here but I've run across another one of these Norton transmissions with the ribbed case. Who made them?
I imagine they were for high strength / racing use, doesn't have the usual numbers. I'm sure you guys in Norton land can fill me in.
Thanks

I wouldn't like to keep that box shiny while its in the bike.

Its a Quaife isn't it ?
External ribs are fine but what did they do about the lack of material between the layshaft and output bearing bores ?

I guess that's a nothing then.

I was thinking Quaife but didn't know if anyone else churned out something similar.

I thought it was RGM? Though the reviews of their box was spotty...Maybe the RGM did not have the ribs.

201 050126 STRENGTHENED GEARBOX SHELLS, (LM25 TF, BEEFED UP AROUND THE BEARINGS, A COMPROMISE BETWEEN NORTON ORIGINAL AND QUAIFE) FITS COMMANDO ETC. £ 240.00

Anyone know one way or the other.

The last case I bought from old brits was a factory A/N upgraded standard box....even better than the 850/MKII case. Definitely more beef around the bearings. These are IMO way better than early 750 commando or the delicate atlas cases...but not cheap/inexpensive.

Ken has mentioned and shown these before.

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