It does remind me of Reynolds Hiduminium, (early 50s) which were mostly longer extensions, around 3 inches.
They were a disaster, just not rigid enough.
Thanks Bagpuss and Keith.
I'm sure Reynolds were stamped or name in the mold. The girder stems certainly and on the main tube. Yes certainly nothing new in cycling.
Looks to well made to be anything like a Philips or Triumph.