Last year I found a fairly long bolt on the deck
... it was about 3/8" Ø and 6" long... I had no idea where it came from.
This Spring I was setting the mainsail
up and took apart one of the Shaefer batt cars... because the leech loaded batten wouldn't go all the in. What I discoved was there was a sort of end fitting which "received" the forward end of the batten inside the batt slide. It had a bolt hole... hmmmm that's the bolt which I found. Of the 4 cars.. there was only 1 with a bolt and one that I found...so 2 have gone missing.. probably on a gybe or something... flailing main when it was coming down.
Now to figure out what function does this bolt have. presumable if you tighten it... the end fitting at the forward end of the batten will be pull aft... and I suppose this would tension the batten against the velcroed flap at the leech... If the battens are short. But they are damn tight as it is.