The hammer Strike consists primarily of striking an opponent with the baby finger side down of a closed fist.   Some of the primary targets include the bridge of the nose, temples, collarbone, base of the skull and side of the neck.  Some of the advantages of striking in the manner include that it's simple to do n avoids the inherent dangers that accompany a normal punch such as broken knuckles, thumbs and damaged wrists. Another advantage to using this strike is that it's a natural movement for the human body and takes advantage of a strong bone long the edge of your hand.

This strike is most effectively done with your wrist straight and rigidly locked.  Use a chopping, whipping like motion.

One of the advantages of using this technique in a self defense situation is its versatility and effectiveness in close quarter attacks.  Bend your hand back at your wrist with your thumb tucked slightly back in and your fingers spread apart.  The strike is delivered with the base or lower part of your hand or the heel of your hand. This technique is especially effective when struck under the chin or underneath your attacker's nose.  It is also effective to throw rapid succession blows in a quick alternating motion to force at attacker back and away from you.

Cup both of your hands and pop your attacker on his ears creating an implosion of the eardrums.  Strike both of your hands simultaneously.  As you strike your attacker's ears whip your hands back.  This type of strike is very painful to the attacker and can be quite damaging.    Frequently, the attacker will grab his head because of the pain he is in following the strike.  A double insanity strike an easily disorient an attacker causing severe and even permanent damage to his eardrums.