Quick Summary
The ONIPAX Anti-Theft Bike Seatpost Clamp is a bicycle seatpost clamp with a 7-Lobe Pin bolt. It is offered in 31.8 mm and 34.9 mm sizes, so the frame outer diameter needs checking before choosing the right version.
This clamp is aimed at buyers who want a seatpost clamp that uses a specialised matching key for removal rather than a quick-release lever. The fitted size and bolt type are the main points to confirm.
Key Details
| Detail | Verified information and buyer relevance | |
|---|---|---|
| Product type | Bike seatpost clamp – a frame component that secures the seatpost area. | |
| Brand | ONIPAX | |
| Sizes | 31.8 mm and 34.9 mm options – check the frame outer diameter before selecting a version. | |
| Bolt type | 7-Lobe Pin bolt – removal needs the matching specialised key. |
What to Compare Before Buying
- Frame size: Compare your frame tube outer diameter with the 31.8 mm or 34.9 mm clamp size.
- Removal method: This clamp uses a 7-Lobe Pin bolt, so make sure the matching key is acceptable for your setup.
- Replacement purpose: Check that you need a seatpost clamp rather than another seatpost fitting or locking part.
Before You Decide
Confirm the frame outer diameter, the chosen 31.8 mm or 34.9 mm size, and the 7-Lobe Pin bolt format before choosing an offer. If you need a seatpost clamp that removes with a standard quick-release lever, this is not that type of fitting.
Follow the manufacturer’s fitting instructions for the exact bicycle frame and clamp size.









