CollectingSnapOn.com

Daily I dig through this dusty old tool room and come up with some old, unidentifiable, and mostly useless tools. Today's find could be useful, but I would like to know how old they are. I looked in a drawer containing taps, dies, and other thread repair items and came up with two boxes of SNAP ON combination tap and die thread chasers. The catalog numbers are TDC-3 and TDC-5. They are supposed to be used "TO SERVICE INVERTED FLARED FITTINGS." One end is the tap and the other end is a die. Only three per box: 3/8-24, 7/16-24, and 1/2-20.

Does anyone know how old these tools are?

Thanks!