Hydro Flask 21 oz Water Bottle — Agave Green Standard Mouth, TempShield Insulated & Leakproof Flex Cap

Hydro Flask's 21 oz Agave Green Standard Mouth is a double-wall insulated stainless steel bottle built to keep cold drinks cold for up to 24 hours and hot drinks warm for up to 12, with a leakproof flex cap and cupholder-friendly shape.

This 21-ounce reusable bottle balances everyday convenience with outdoor durability. It slips into most cupholders, fits easily in packs, and its durable stainless-steel construction resists flavor carryover so each refill tastes fresh. The flexible handle on the leakproof cap makes it simple to grab or clip onto gear, while TempShield double-wall vacuum insulation preserves temperatures for long stretches.

How well does it keep drinks cold or hot?

The Hydro Flask 21 oz uses TempShield double-wall vacuum insulation engineered to slow heat transfer. Expect cold beverages to stay chilled up to 24 hours and hot drinks to remain warm up to 12 hours under typical conditions. Insulation performance may vary with fill temperature and ambient conditions.

• Double-wall vacuum keeps temperature steady.
• Ideal for long commutes, workouts, or day hikes.
• Stainless steel interior prevents flavor retention.

Is the bottle leakproof and easy to carry?

The included Hydro Flask Flex Cap seals securely to prevent leaks when closed and features a flexible handle for comfortable carrying. Toss the bottle into a bag or attach the handle to a carabiner for hands-free transport. The cap design prioritizes both a tight seal and simple one-handed grip.

• Flex Cap provides a leakproof closure when tightened.
• Flexible handle for easy hand-carry or attachment.
• Lightweight design suitable for daily use and travel.

Will it fit in cupholders and backpacks?

The 21 oz Standard Mouth profile is shaped to sit securely in most vehicle cupholders and standard backpack side pockets. Its size gives a comfortable balance between capacity and portability—large enough for hours of hydration but small enough for compact storage. The low-profile base keeps it steady in trays and cup mounts.

• Cupholder-friendly diameter for car or stroller use.
• Compact height fits many backpack pockets and organizers.
• Stable base reduces tipping on flat surfaces.

How do I clean and maintain this bottle?

The bottle and lid are dishwasher safe for straightforward cleaning; rinse before placing in the dishwasher to remove residue. Stainless steel construction resists staining and odors, helping every refill taste fresh. Replace caps or gaskets if they show wear to keep the seal reliable.

• Dishwasher-safe components for easy cleaning.
• Stainless steel interior resists flavor transfer.
• Inspect seals periodically and replace if needed.

Who this bottle is for: anyone seeking a dependable everyday bottle that bridges active outdoor use and daily routines. It suits commuters, gym-goers, parents, students, and weekend adventurers who want durable insulation, a leak-resistant cap, and a size that fits cupholders and pack pockets. If you want a reliable, reusable bottle in a distinctive agave green that keeps beverages tasting pure, this Hydro Flask 21 oz is designed for that role.