This 1/16" clear, smaller diameter dustwasher for Sanwa JLF is a popular choice amongst customization fans. At 31mm, it remains just a bit larger than the joystick opening, but keeps the hole covered properly during gameplay.
This version is sized for a Sanwa JLF joystick without shaft cover.
The dustwasher is protected from scratches and dust by a brown paper sticker. You can remove the paper sticker by peeling at the edge of the dustwasher with your fingernail, and pulling towards you.