Hi all - I love my Nakaya pens, but when I'm working and not at my desk (my desk is in the attic and under the virtually uninsulated roof it's hot), I am annoyed by screwing tops on and off. So I wonder if anyone with the Platinum slip and seal top can tell me - can you just slide the cap on and off? From the photos it looks as if they have threads. If one can just slip the cap on, that would speed up things a lot.

Many thanks!