飛行機に水筒・マイボトルを持ち込める？（米国TSA・CATSA規則）

持込可：100ml（3.4オンス）以下の容器に入れ、容量1L以下のジッパー付き透明プラスチック袋に収納してください。

受託手荷物：預け入れ可能です。100mlを超える大型ボトルもスーツケースに入れて預けることができます（スプレー類の制限に注意）。

Limited to what fits inside a single 1-quart (1-liter) transparent resealable bag in carry-on.

Yes, passengers may use Water Bottle during flight in compliance with crew instructions.

Yes. Major brands such as Hydro Flask, Stanley Quencher, Yeti Rambler must comply with standard security limits based on physical properties rather than brand labels.

Standard toiletries and liquids conforming to the 3-1-1 rule (containers under 3.4 ounces / 100 ml inside a clear quart bag) require no separate declaration. You simply place the bag in a screening bin. Medically necessary liquids exceeding 3.4 ounces must be verbally declared to checkpoint screeners before inspection.

If liquid containers exceeding 3.4 ounces (100 ml) are detected in carry-on baggage without an infant or medical exemption, screeners will not allow them past security. Travelers must surrender the item for destruction, return outside security to place it in checked luggage, or mail it home.

An empty bottle, yes — through any US or Canadian security checkpoint. A filled one, no, unless it is frozen completely solid at screening.

Yes, an empty water bottle of any size or material (stainless steel, plastic, insulated) is permitted through airport security checkpoints. Water bottles filled with liquid over 3.4 oz (100 ml) must be emptied before screening; you can refill them for free at terminal hydration stations after security.