Great idea, very clever! However the reason there are so many seats on the market is because everyone has a different preference when it comes to seat comfort. I think it might be better to make the seat post as the integrated lock and not the seat itself.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth