We have worked hard to modify these refillable travel containers and tested the heck out of them to ensure they don?t leak. Gotrippin travel cosmetic bottle set is made of FDA approved and BPA free food grade silicone, making it safe for other liquids like sauce, salad dressing or even baby food. All of our travel size bottles for toiletries are see-thru; and well under the 3.5 ounce / 100 ml restriction for taking onto all airline planes. Each of the empty bottles for liquid is 100% reusable, so you can travel with this travel kit bottle set over and over again!