There are powered extractors, and there are hand pumped vacuum extractors. You pump them up and create a vacuum. The tube has a clamp. Once you reach the specificied number of pumps you stick the tube in and release the clamp.

The tube needs to be fairly thin in diameter. The plastic needs to be somewhat heat resistant. You don't want to melt the end on the pan. Also the end of the tube should be cut at 45 degrees or so. This is to prevent the end of the tube from sealing to the bottom of the pan.

Steve