The item for sale here is an NOS 12 Volt Voltage Regulator.  Not sure the interchange on this but believe it will fit most 1960-64 GM, AMC, Rambler and GMC.  Please make sure this fits your application.

This is NOS new in the original box.  Kind of a cool part as this is an NOS Prestolite part that was repackaged in a Mopar box sold at Chrysler dealers.  Found this in an old closed down dealer in a Mopar cabinet filled with tune up and NOS parts.  It is part number 8-221, P8-221, and DR-500 (Mopar number).

Shipping is a flat rate of $13.50 in the US, $25.00 to Canada and $35.00 elsewhere.  Buy more items from us and we will gladly combine shipping!