Manufacturer dimensional interchange
Falk / Rexnord 04UCBN2 appears in the same manufacturer-published cross-reference row as Flender/Motox Z30 at Verify motor speed and installed ratio · Ultramite size 04.
Falk/Rexnord Form 950-501 publishes 04UCBN2 in its base-mounted helical dimensional comparison for size 04. The guide states that several competitive helical designs are drop-in replacements but instructs users to verify motor speed, gear ratio, output RPM, mounting position and current catalog ratings. Availability of this historical configuration should also be confirmed.
The manufacturer publishes the two models in a dimensional-interchange table or equivalent dimensional comparison.
Flender/Motox Z30 and Falk / Rexnord 04UCBN2 are tied by the published source at Verify motor speed and installed ratio · Ultramite size 04.
Dimensional alignment does not by itself prove identical torque, thermal rating, service factor, ratio, accessories, or application suitability.