Great idea and the first time I have seen something like this. For those odd ball connectors that are on the Tomy/Plarail Turn Tables. Don't know why they have both type of connector on the turn tables. My only guess is that they wanted the odd connectors to go to the included sheds as dead end rails.
https://www.jauce.com/auction/q372419939
https://www.jauce.com/auction/q372419939