Weston 128544 power transformer NOS from 1956! Military? 5950006477399 006477399

Description

This is a Weston 128544 power transformer which until today was still sealed in the original packaging from 1956. I carefully cut open the bag only to photograph it. This component is something of a mystery to me.  Here is the exact info printed on the packaging:
N17-73646-6833
TRANSFORMER POWER: P/N 128544
ONE UN:EACH
N126s-70354(P)
WS NEWARK, N.J. MFG/CONTR
WESTON ELEC. INSTR. CORP. NEWARK, N.J
DATE PKD. 4/56 METHOD II C
The packaging is from the Continental Can Co., Inc,  Shellmar-Betner Div, dated April, '54 on one side and July, '54 on the other. This packaging seems military-related to me and the desiccant pack also has a military spec number on it, so I strongly suspect this transformer was for military use.
This seems to be a substantial transformer, weighing nearly 4 pounds. I do not know the specs, sorry. From a google search, I'm seeing alternate part numbers of: 5950-00-647-7399, 00-647-7399, 5950006477399, 006477399.
The transformer is is new, unused condition. The humidity indicator inside the sealed package does display slightly pink circles, but this may just be an artifact of decades of sitting. I see no evidence of any sort of moisture exposure nor any physical damage to the transformer.
This is a recent estate find from a meticulous home workshop that had lots of vintage NOS electronic components, some dating as far back as the 1950s.
I have no way to test this component. All sales final given the nature of vintage electronics. Please look through the pictures and ask questions before bidding.