坐飞机可以带 一次性剃须刀与替换刀头 吗？（美国TSA/加拿大CATSA标准）

有限制允许：一次性剃须刀及一体式卡式刀头剃须刀（如吉列）允许随身携带；双面老式剃须刀片及直剃刀严禁随身，必须托运。

允许托运：所有类型的剃须刀及备用刀片均可托运（请妥善包裹刀刃防止划伤）。

Standard carry-on baggage size allowances apply; TSA publishes no individual numerical cap for personal use.

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.

CATSA: Yes — disposable razors and blade cartridges is allowed in carry-on baggage through Canadian security checkpoints. In checked bags: Yes — allowed in checked baggage with proper packaging.