You might be concerned about using travel size bottles because you're wondering if the small sizes will last for an entire trip. This really depends on how long you'll be gone.When it comes to things like shampoo and body lotion, a 3.4 oz bottle should be plenty for a one week trip, and you'll need much less of items like face wash and face lotion.Longer trips often call for a checked bag, and in that case, there’s nothing wrong with packing larger sizes of items you know you’ll use more of. Just leave room for souvenirs!