The park one is a less cheap bit of plastic, I can't really think how you'd improve upon a roughly the right sized slot in a hard plastic or similar material to make the tool.
@snottyotter started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
The park one is a less cheap bit of plastic, I can't really think how you'd improve upon a roughly the right sized slot in a hard plastic or similar material to make the tool.