Flat Cap - 42mm

Replacement Cap
2.8
Rated 2.8 out of 5 stars
30
$5.00
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Flat Cap - 42mm

Product Details

This is a replacement cap for the Stash 750ml bottle and the Seeker water storage container in sizes: 2L, 3L, 4L, and 6L.

 

Please note that this cap is not compatible with any of our SoftFlasks and does not fit the Seeker 10L.

 


Camping Hiking

Reviews

2.8
Rated 2.8 out of 5 stars
Based on 30 reviews
Reviews Summary
Customers say this flat cap works well with certain bottles and newer models, though compatibility varies significantly. Many report leaking issues with soft flasks, particularly older models, while others find it performs without problems on compatible bottles. Some users mention adding an extra o-ring improves sealing on soft flasks. A few note the cap cracked or broke during use. Compatibility appears dependent on bottle model and purchase date, with mixed experiences across different flask brands.
43%would recommend this product
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30 reviews
  • SA
    S A. E.
    Verified Buyer
    Reviewing
    Flat Cap - 42mm
    I do not recommend this product
    How old are you? 45 to 54
    What is your gender? Male
    Rated 2 out of 5 stars
    3 months ago
    Not compatible with Solomon Hydrapak.

    I purchased the flat cap for use with the Hydrapak 500 mL soft flask speed and Hydrapak soft flasks 500 mL that came with my Solomon vest. The caps worked without issue on the soft flask speed, but would not seal correctly and leaked with the soft flasks that came with my Solomon vest.

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    HydraPak
    3 months ago

    I am sorry to hear that your soft flasks leaked. Please reach out to our warranty team to send you out a replacement here:

    https://support.hydrapak.com/hc/en-us/requests/new?ticket_form_id=913128,Customer Experience,clientresponse

  • J
    Julia
    Verified Buyer
    Reviewing
    Flat Cap - 42mm
    I recommend this product
    How old are you? 25 to 34
    What is your gender? Female
    Rated 5 out of 5 stars
    1 year ago
    Flat Caps for all Flasks!

    I love my flat tops that work great with all of my hydrapak branded flasks. Including Solomon and tailwind models!

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  • R
    RichardAAbel
    Reviewing
    Flat Cap - 42mm
    I recommend this product
    How old are you? 35 to 44
    What is your gender? Male
    Rated 5 out of 5 stars
    1 year ago
    Did not leak, Seeker 2L

    I was hesitant after all the reports of leaking. Did not leak on my Seeker 2L.

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  • D
    domlazz
    Verified Buyer
    Reviewing
    Flat Cap - 42mm
    I recommend this product
    Rated 5 out of 5 stars
    1 year ago
    Need a 42mm cap? This is it!

    I have many 42MM bottles that match with my water filter device. Some of them have cheap lids I don't trust. I got this to replace those. It works great and looks quality.

    Was this helpful?
  • V
    Veraun
    Verified Buyer
    Reviewing
    Flat Cap - 42mm
    I recommend this product
    Rated 5 out of 5 stars
    1 year ago
    Add an o-ring to work with soft flasks…

    Agree with an earlier review that adding a second o-ring to these makes them work leak free on 42mm soft flasks.

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