Morris Minor Owners Club

Can you please advise what the little o ring type rubber is in this kit as don't remember seeing one when I out mine back together.Where would it go more to the point please.

The ring seal is for the alternative after market piston fitted to some slave cylinders.
https://www.moss-europe.co.uk/repair-ki ... soc=730567
If your slave cylinder does not have the ring seal ditch the ring seal.

Thanks very much.