This is a French (or Swiss) threaded Bottom Bracket for use with 24mm axle cranksets (Shimano Hollowtech compatible).
Millions of vintage bikes have French threaded or Swiss threaded bottom brackets.  Used and new square taper bottom brackets are still available, but there is (almost) no solution to install a modern crankset with a 24mm spindle on those frames.
Our BB is custom produced by a respected Taiwanese producer and uses quality steel bearings.
The French threaded BB uses 35x1mm metric threads right-handed on both sides.
The Swiss threaded BB uses 35x1mm metric threads a right-hand thread on the left and left-handed on the right (to avoid the cups to unscrew themselves).
95 grams