Hydro Flask 21 oz Standard Mouth Flex Cap Bottle
Black / 21oz
$24.47
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For shorter runs, day hikes, and gym sessions where a full liter is overkill, this is our go-to bottle for athletes who want cold water without the bulk. TempShield double-wall vacuum insulation keeps drinks cold for 24 hours — no sipping warm water by mile three in August. The flex cap clips to a pack or vest so your hands stay free on the move.
Hydro Flask 21 oz Standard Mouth Flex Cap Bottle
$24.47
- TempShield double-wall vacuum insulation holds drinks cold 24 hours and hot up to 12 — no condensation on the outside, no warm water mid-run
- 21 oz sits in the sweet spot between too heavy and not enough — enough for shorter runs, day hikes, and gym sessions without dead weight
- 18/8 pro-grade stainless steel won't hold flavors or odors after days of use; powder coat finish keeps your grip solid even with sweaty hands
- Standard mouth opening works with most inline water filters and is wide enough to clean properly after muddy trail days
- Flex cap carry loop doubles as a clip point — attach it to a pack, vest, or carabiner when you need both hands free