A beautiful tested set of 1950s production era Western Electric 441A 1mf caps. WECO spcified very conservative voltage ratings on all of their caps. Most paper wax / bakelite caps of this era and size, were Hi-Pot tested at 500V. Western Electric wanted continous duty at no more than 200V. 

One pc is from 1951, and the other from 1959. They test beautifully, better than new with very low ESR and no leakage, and rated continous 200V. I am sure they could handle lots more for brief periods, but for that use, go with oil types. These Silver / Alum extruded designs were proposed by WECO pre WWII back in the 1930s, they did not start production until postwar 1940s onward. 

  CAPS Guaranteed NO DOA. 

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