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Hydro Flask 21 oz Standard Mouth Flex Cap

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Hydro Flask Standard Mouth Flex Cap, Pineapple, 21 oz, S21SX750
Hydro Flask Standard Mouth Flex Cap, Alpine, 21 oz, S21SX433
Hydro Flask Standard Mouth Flex Cap, Carnation, 21 oz, S21SX622
Hydro Flask 21 oz Standard Mouth Flex Cap, Rain, S21SX417
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
Hydro Flask 21 oz Standard Mouth Flex Cap, Starfish, S21SX827
Hydro Flask 21 oz Standard Mouth Flex Cap, Seagrass, S21SX321
Hydro Flask 21 oz Standard Mouth Flex Cap, Laguna, S21SX454
Hydro Flask Standard Mouth Flex Cap, Alpine, 21 oz, S21SX433
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
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Hydro Flask Standard Mouth Flex Cap, Pineapple, 21 oz, S21SX750
1 of 12 images
Hydro Flask Standard Mouth Flex Cap, Pineapple, 21 oz, S21SX750
Hydro Flask Standard Mouth Flex Cap, Alpine, 21 oz, S21SX433
2 of 12 images
Hydro Flask Standard Mouth Flex Cap, Alpine, 21 oz, S21SX433
Hydro Flask Standard Mouth Flex Cap, Carnation, 21 oz, S21SX622
3 of 12 images
Hydro Flask Standard Mouth Flex Cap, Carnation, 21 oz, S21SX622
Hydro Flask 21 oz Standard Mouth Flex Cap, Rain, S21SX417
4 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Rain, S21SX417
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
5 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
Hydro Flask 21 oz Standard Mouth Flex Cap, Starfish, S21SX827
6 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Starfish, S21SX827
Hydro Flask 21 oz Standard Mouth Flex Cap, Seagrass, S21SX321
7 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Seagrass, S21SX321
Hydro Flask 21 oz Standard Mouth Flex Cap, Laguna, S21SX454
8 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Laguna, S21SX454
Hydro Flask Standard Mouth Flex Cap, Alpine, 21 oz, S21SX433
9 of 12 images
Hydro Flask Standard Mouth Flex Cap, Alpine, 21 oz, S21SX433
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
10 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
11 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604
12 of 12 images
Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604

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Questions & Answers

Product Discontinued by Manufacturer

Hydro Flask 21 oz Standard Mouth Flex Cap has been discontinued by Hydro Flask and is no longer available. Our product experts have helped us select these available replacements below.You can also explore other items in the Outdoor Gear, Hydration, Water Filtration Systems yourself to try and find the perfect replacement for you!

Product Info for Hydro Flask 21 oz Standard Mouth Flex Cap

When you want your water to stay piping hot or ice cold for up to 24 hours, you need the Hydro Flask Standard Mouth Flex Cap. Leak-proof and made of durable polypropylene PP#5, this cap fits any standard mouth bottle. This allows the trapped hot vapors to escape, keeping your hands comfortably cool as you sip on your favorite beverage. With a vented cap, the Hydro Flask 21 oz Flex Cap allows the air to pass through so you can enjoy a piping hot drink without having to crack open your bottle. You'll be ready for any adventure when you're fueled by the Hydro Flask Standard Mouth Flex Cap.image

Features of Hydro Flask Standard Mouth Flex Cap:

  • Leak-proof design
  • Vented cap allows hot vapors to escape
  • Made of durable polypropylene PP#5
  • BPA-free
  • Compatible with all standard mouth bottles
  • Lifetime Warranty

Package Contents:

  • Hydro Flask 21 oz Standard Mouth Flex Cap

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Hydro Flask 21 oz Standard Mouth Flex Cap Unavailable & Discontinued Models

List of Unorderable Models

  • Hydro Flask Standard Mouth Flex Cap, Pineapple, 21 oz, S21SX750 , MPN: S21SX750 , UPC: 810028842397 , Code: HDF-WBA-HYF003621-S21SX750
  • Hydro Flask Standard Mouth Flex Cap, Carnation, 21 oz, S21SX622 , MPN: S21SX622 , UPC: 810028842373 , Code: HDF-WBA-HYF003621-S21SX622
  • Hydro Flask 21 oz Standard Mouth Flex Cap, Seagrass, S21SX321 , MPN: S21SX321 , UPC: 810070081812 , Code: HDF-WBA-HYF003621-S21SX321
  • Hydro Flask 21 oz Standard Mouth Flex Cap, Laguna, S21SX454 , MPN: S21SX454 , UPC: 810070081829 , Code: HDF-WBA-HYF003621-S21SX454
  • Hydro Flask Standard Mouth Flex Cap, Alpine, 21 oz, S21SX433 , MPN: S21SX433 , UPC: 810028842380 , Code: HDF-WBA-HYF003621-S21SX433
  • Hydro Flask 21 oz Standard Mouth Flex Cap, Snapper, S21SX604 , MPN: S21SX604 , UPC: 810070081836 , Code: HDF-WBA-HYF003621-S21SX604
  • Hydro Flask 21 oz Standard Mouth Flex Cap, Starfish, S21SX827 , MPN: S21SX827 , UPC: 810070081843 , Code: HDF-WBA-HYF003621-S21SX827
  • Hydro Flask 21 oz Standard Mouth Flex Cap, Rain, S21SX417 , MPN: S21SX417 , UPC: 810028842403 , Code: HDF-WBA-HYF003621-S21SX417
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Last updated 2026-07-20 UTC.