I left on vacation thinking I had all my CPAP supplies with me. Found out the first night I had left the elbow behind. When I arrived at Ft Lauderdale, I did a Google search and found SleePlay office near me and the had the Airfit F20 elbow in stock. Purchased it and have been sleeping great ever since. The Airfit F20 elbow is quiet and works great with my mask. Wouldn’t use anything else!