Specialized S-Works Sitero saddle · Vertical Dual Bottle — side installation view
RSTRI Triathlon Saddle Rear Hydration System
Triathlon saddles differ in more than shape. Rail geometry, rear width and available mounting space all determine how a rear hydration system can be positioned. Rather than forcing one universal bracket onto every saddle, RSTRI develops saddle-specific solutions with single-bottle, vertical dual-bottle or side-by-side dual-bottle layouts according to the space actually available behind the rider.
01 / Design
Rethinking the space behind each saddle.
Triathlon saddles differ in more than shape.
Rail geometry, rear width, available mounting space and the rider's actual saddle position all affect where a rear hydration system can sit. Instead of trying to make one universal bracket solve every case, we design the mounting solution around the saddle itself.
The RSTRI Triathlon Saddle Rear Hydration System is designed to keep bottles compactly positioned behind the saddle and rider while maintaining practical bottle access, secure mounting and real-world usability.
Depending on the saddle and the space available, the system can use a single-bottle, vertical dual-bottle or side-by-side dual-bottle layout.
There is no single layout that needs to work for everyone. What matters is finding the layout that works properly for that saddle.
Saddles, bottles and bottle cages shown in the images are installation examples. Confirm the supplied components in the product details or with RSTRI before ordering.
- Product brand
- RSTRI
- Product type
- Rear Hydration
- Verified bike records
- 0
- Product images
- 20
02 / Compatibility
Compatibility starts with the saddle.
Mounting structures and hydration layouts vary between saddles. The gallery shows installation photos for the Specialized S-Works Sitero and ISM PN 4.0, along with examples involving some WOVE and Selle Italia saddles. The brand, saddle-model and hydration-layout tags filter photos; they do not certify compatibility. There are specific photos of a vertical dual-bottle layout on the S-Works Sitero and single-bottle and side-by-side dual-bottle layouts on the ISM PN 4.0. Exact WOVE and Selle Italia models remain unconfirmed. Other photos should not be used to infer compatibility with an unlisted saddle. Before ordering, contact RSTRI to check your saddle model, mounting space and available solution.
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