This set of (2) Collins 516F-2 NOS Drop in Tube Socket Replacements, are original, New old stock tube sockets, which mean they will drop right in and use the same mounting holes. You do not have to modify or drill new holes!
Collins used different shades of brown through the years, so they are sold in Pairs. I have only a few sets left!
Do not wait to pick up a set to replace your cracked or burnt tube sockets or to have a spare set on hand as they will not last long!