Flip Cap 28mm vs Other HydraPak Caps: A Guide
By HydraPak | Performance Hydration Reservoirs, Soft Flasks ... | Published: 2026-10-26
Category: Comparisons
Compare the Flip Cap 28mm with other HydraPak caps to find the best replacement for your bottle or flask. Learn about compatibility, features, and trade-offs.
Quick answer
The Flip Cap 28mm is a great choice if you want a self-sealing silicone nozzle with a protective cover, but it only fits 2020 or newer HydraPak bottles and flasks with a 28mm opening. For older models or different needs, consider other HydraPak cap options.
Why cap compatibility matters
HydraPak updated the thread design on its 28mm openings starting with 2020 models. Caps made for the newer threads will not fit older bottles and flasks, and vice versa. Before buying a replacement cap, check the manufacture date or thread version of your HydraPak product.
Trade-offs with the Flip Cap 28mm
The Flip Cap 28mm offers a convenient auto-sealing silicone nozzle that stays clean under a flip-top cover. This design is ideal for quick sipping during activity. However, the silicone nozzle can be chewed or damaged over time, and the flip cover adds a small moving part that could break. Also, it is not compatible with older HydraPak threads.
Flip Cap 28mm vs other HydraPak caps
- Flip Cap 28mm: Auto-sealing silicone nozzle with flip-top cover. Best for: quick, one-hand sipping during runs or rides. Not for: older (pre-2020) HydraPak bottles or flasks.
- Standard screw cap (28mm, newer models): Simple, durable plastic cap with a tethered top. Best for: users who want a no-fuss, reliable seal and don't need a drinking spout. Not for: those who want to drink without removing the cap.
- Older 28mm caps (pre-2020 models): Threads are not compatible with the Flip Cap 28mm. Best for: owners of older HydraPak gear who need a direct replacement. Not for: anyone wanting the features of the new Flip Cap. Check your bottle or flask for the manufacture date or thread version before ordering a cap.
Product facts
- Flip Cap - 28mm: This replacement cap features an easy to drink from silicone nozzle which auto-seals after each sip and includes a flip cap cover to keep away outside elements. Fits all current HydraPak products with a 28mm opening including the Stow 500ml and 1L bottles, and SoftFlask 150ml. Note that caps only fit on the 28mm threads of 2020 models or newer. If you own a HydraPak product from 2020 or later with a 28mm opening, this cap gives you a clean, one-hand drinking experience. If your gear is older, this cap will not fit.
Flip Cap - 28mm
Which cap fits your gear?
Best for
- Owners of 2020 or newer HydraPak bottles and flasks with a 28mm opening who want a self-sealing, covered drinking spout
- Active users who need one-hand hydration during runs, rides, or hikes
Not for
- Owners of pre-2020 HydraPak products (the Flip Cap 28mm will not fit)
- Users who prefer a simple, no-moving-parts cap and don't need a drinking spout
