We are permitted only to supply this product to a hospital, bar or restaurant, for provision to people with disabilities or medical conditions that require them. These straws have one-way valves which stay filled with fluid, even after removing the straw from a users lips. This feature eliminates the possibility of sucking in too much air while drinking. The clip-on straw hooks onto the side of a glass or cup to prevent the straw falling out. Each package contains two straws, one 254mm (10") and one 178mm (7").