The old o ring design and the newer rubber sleeve design.
The sleeve has proven to be a better design. Sleeve design requires a new dipstick tube with a smaller end to accept the sleeve.
If you use the old style o ring design make sure the tube is perfectly round and not oval. I’ve seen many tubes that were oval because someone worked the tube back and forth. Once it’s oval nothing with seal it up, not even a tube of RTV.
