Please help me identify this random bit of plastic that may be part of a toy

[mammmamia]

Having a bank holiday clear out and came across these yellow plastic things. Don’t want to throw them out as I don’t know what they belong to. Any ideas?

DS used to have some little cars that you put something like that into the back of, pulled them out and it made the car shoot off

They're obviously incredibly versatile doodahs, op! Thank God you didn't bin them

@LyndaLaHughes that’s it! We had a bouncy castle from ELC and they belong to that. Thank you!

@Thisismytimetoshine Quite. I shall retain these incredibly useful doodahs and no doubt when I come across them again in five years’ time will be posting here again asking for help to identify them.