Date of Manufacturing / Production Code for SR seatposts (at least for the 80's):
The date of prodcution of SR (Laprade) seatposts is shown around the min.insert line as follows:
"letter"-"double digit number", e.g. F-81 oder
L-81, while the letter should be the month and the number will be the year
of production.
So F-81 seems to be June 1981 while L-81 would indicate December 1981.
(in-line with the code 1 examples on vintage-trek.com...)
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