Before purchasing this, consider what tubing you have on-hand. While this siphon works great, most of my tubing was better-suited for the 3/8" option that MoreBeer also sells:https://www.morebeer.com/products/easy-siphon-38-inch.htmlI had no 1/2" ID tubing and needed to go purchase some. The 1/2" ID can be quite stiff and, when getting a length suitable for siphoning, can be cumbersome.So... That said, the cap at the end of siphon is a necessary and welcome component. Make sure you don't lose it! While the sipon will work without it, it helps reduce the amount of trub sucked in and works especially well when using a fermenter with a convex bottom.