The same as using the Two-On-One you  can secure  the  high single from the under hook. All the rules of shooting from two-on-one apply. Circle away from  the leg you are going to attack  while pulling your opponent toward you with your under hook. As soon as he steps forward to  regain his balance,  drop your level  and snatch his leg.

Your head positioning has to be right under your opponent head to give you control of the position.