Knee in the stomach, knee in the belly I call it sometimes. This is a control position here and here. OK. To get to this position, I start from the side mount. I hop up. My leg is up. This is not a knee in the belly. Right here, the floor is carrying my weight. I want my opponent to carry my weight so I'm going to be up on my foot there. Here and here.
Now we're going to go for a choke in the knee and the stomach. Here, open his collar. Four fingers in, one thumb out. Here my other hand goes over. And notice I'm grabbing the shoulder. My hand is tight against his neck. I'm not just grabbing here. That's a lot of space. Right here. If his gig was open I'd put one thumb in and do it like so, but a lot of time it's tight.
You could just grab the fabric on the shoulder right by the neck, right by the throat here. I'm going to pull my elbows towards my rib cage as I put my head down by his head. Hands together. Do not do this. That's wrong. Elbows must go towards my rib cage. And I put my weight down. And that's your choke from the knee and the belly.