The Aftec extractor is the absolute best extractor in the world!
Most extractors' power is made from the tension it has created. A normal extractor is made from a semi-malleable material, and the gunsmith would bend it just enough to create that tension. But, of course, if the extractor can be bent one way, it can be bent the other. What happens is that the reverse tension on the extractor causes it to bend away from the intended angle, thus losing that needed tension for extraction. But, the Aftec extractor is totally different and ultimately redesigned. It is made from a much harder, non-malleable material. You'll also notice that the Aftec has two holes in it. It also comes with two tiny springs and a sleeve. The springs insert into the holes, and the sleeve fits over the top of them. This unique assembly creates a great amount of tension without weakening your extractor by bending it. The springs may wear over time, and are easily replaced, but your Aftec extractor will be the most reliable and consistent extractor you'll ever own!
Thanks DD could not have said it better myself.