The choices are adjustable or fixed.
Then look at the threads most are threaded on both sides, Male x male are the most common.
Usually they fail when the soap is left to dry inside the mechanism. Most of the time they can be resurrected by disassembling and cleaning off the dried soap and then reassembling.
The spring inside can be easily lost when you take it apart.
It’s a good practice to rinse with clean water after each use to avoid the soap build up that dries and causes the spring, o-ring and ball to seize up.