This is for 10ea RC Capacitors 3400 pf 800 Volt 10%. Body is ~3/4" long, ~3/8" diameter. Good stuff molded epoxy housing, core wound polystyrene. The part specifics are encoded in the part number which is GTE Lenkurt 253 (Polystyrene) 2 (axial lead) 6 (800V) 340 (value MSD) 1 (number of zeros) 4 (tolerance 10%). Lenkurt manufactured telephone carrier equipment which called for high quality, accurate filters with service life measured in decades.

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