Mine is a 3/8" female thread - male barbed fitting. Take your female end-cap off and take it to a hardware/auto store to make sure it fits the male thread on the remote drain tube. And size the barbed end to match your extractor tubbing ID. I just screw it on hand-tight and it seals well. Maybe a little twist with a wrench to make sure it doesn't leak.

That extractor is a MityVac 07400....but since then, I've switched to a "Panther 75-6015p" 15 liter extractor. Much better build quality and holds a lot more fluid. I added a larger 1/2" OD poly tube and a 3/8" male barbed ball valve in the middle of the tubing. I can build up a vacuum, then open the ball valve for super fast drains. Just for fun, I've been trying to see how fast I can drain oils in stuff. I just drained my boat in less than 20 seconds with hot oil after a ski run. The ridiculous speed is mostly for fun and shows friends how easy the oil changes are with an extractor. I'll let it sit for a while and pump it a few times more once the rest of the oil settles to the bottom of the pan. only a couple ounces come to in the end. I'll make another video with the new Panther extractor.