This is a vintage Heath high voltage power supply from the 1950s-1960s era. 0-500VDC, regulated. Current regulating (metered).Also has 6.3VAC output for tube filaments as second channel. It has meter adjustment for calibration. Partial manual copy provided.Tube complement and operation info given in photos. Did not check for ripple, but I would change electrolytic caps at some point as they are probably 60 years old. I have been using it all along for vintage radio and amplifier work w...ith no issue. Shipping via FedEx Ground or FedEx Home Delivery, cost based on buyers location from 27916. About 15# shipping. All shipping appears to be longer than usual.Buy It Now disappears as soon as someone opens a bid. PayPal only, thanks! Case shows some wear and a minor dent but overall good for age.