This is a silicone container from humangear, very popular in the US. I used it to hold olive oil during mountain climbing. It has been washed. The capacity is 53ml. The size is approximately 5x8.3x3.8cm. It can be used for travel to hold shampoo, or for camping to hold food like ketchup. You can extend the hook to hang it, or pass a carabiner through it for carrying. Extending the hook also acts as a double lock to prevent the lid from opening. It stands on its own, making refills convenient. There is also a space for a label. The opening is wide, so you can wash the inside thoroughly.