Originally Posted by
yellowjeep
Open/close is just the quick release. If it is a DA hub it is (or should be) Both HG and UG compatible.
Why would there be an open and close on the hub seal for the quick release? I just read that Dura Ace had to diameter hubs at this time. That You Shimano for making it easy! Should be both, I agree. Better minds will enter here soon, I hope.