Can anyone ID these seat tracks

I've been talking to Barry Washington about a set of seat tracks I have. They do not have any stops on the inside tracks or any release spring levers on any of them. Any idea what they are for?

I believe in 72, on the e-bodies for sure the inner tracks no longer had the lock position like the 70 and 71's. Supposedly this was a safety issue during a crash. There should be a date code somewhere on the flange that mounts floor side, this may be able to shed some light as well.

Mike Afflerbach

1972-73 E-body.

OK guys yes you are both right. There is a date code on the bottom of the inside track of 72 Thanks guys