Originally for the 86-91 N/A Rx7 3rd and 4th gear, but will also fit earlier 81-85 12A transmissions as well.

From on of our customers:

"
Hi there, just letting you know that I've ordered M501-17-404D on an order from you, which is listed as 86 to 91 NA Rx7 3rd 4th selector fork. I have a photo here but I can't attach it unfortunately. I just want to let you know that it is identical to 81 to 85 Rx7, including HB and HC Cosmo/Luce 12a turbo gearboxes. So if you want you can add that in the information. I'm about to rebuild a 1981 to 1983 S2 Rx7 gearbox and the 3rd 4th fork is identical to the listed 86 to 91 NA rx7 3rd 4th fork. Cheers!!!
"