He is considered to be one of the best in the world at leg locks, such as the heel hook and kneebar.

There he defeated Neil Grove after applying a heel hook.

Eventually, he got caught in a very tight heel hook and could not escape and was forced to tap.

He was submitted in the first round via heel hook.

Herman defeated Noke by submission (heel hook) in the first round.

The round ended with Fedor trying his own heel hook.

LaRosa won the fight via submission from a reverse heel hook early in the second round.

Watch him finish off Hernandez (3:44 mark) with a nifty heel hook.

The heel hook is generally considered to be a very dangerous leg lock, with a high rate of injury, especially to ligaments in the knee.