Those are elarly versions of the oil impregnated Black Beauties, no fun to be around when they fail..... 
http://www.33audio.com/enter/data/Sprague56paper.pdf
Cheers,
__________________
Brian
USN RET 22YRS (Avionics/Cal)
CET-Consumer Repair and Avionics ('88)
"Capacitor Cosmetologist since '79"
When fuses go to work, they quit!
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