A hose clamp Oetiker 15 x 18 is a type of clamp that is used to secure a hose to a fitting or nipple. It is made of a durable material, such as stainless steel or aluminum, and has a unique design that allows it to provide a tight and secure seal. The clamp has a diameter of 15mm and a clamping range of 15-18mm, which makes it suitable for hoses with an outer diameter of 15-18mm.