I use several bags from BottleWise. The singles ones work great for all different shapes. Plus if TSA opens your bags and undoes your packing, your bottles are possibly left unprotected. These bags open and close easily so if you get stuck with a someone from TSA trying to prove something, they can see that your bottles are sealed in a liquid proof container. Otherwise you take the chance of them taking them away. Found this promo from BottleWise http://tinyurl.com/yha9szz