This is an "BC" / "ZD" pair manufactured in 1975/1977, and so, average 46 years old. Please see a detailed photo with the year code and check the table bellow. The date code is stamped into the component and appears separately from other markings. The code is on the outer flange or the center shaft of hubs. The first letter represents the year and the second is the month, where A is January and L is December.
For the first letter A is 1976 and the letters proceed sequentially from there: K is 1986 and Z is 2001. Year 2002 restarts with A. The item "1975/7 NOS Shimano DuraAce Pro Model Front/Rear HUB Large Flange 24H Spoke Holes" is in sale since Thursday, May 28, 2020. This item is in the category "Sporting Goods\Cycling\Bicycle Components & Parts\Hubs". The seller is "andrer01" and is located in LOURES.This item can be shipped worldwide.