Won-hyo step 27 and 28 are inside outer forearm closed fist blocks at mid height. These are taught as over the shoulder throws. The pre-requisite to learning or applying this is the ability to do a breakfall in the air, forward rolls, and forward rolls ending with a slap to the ground.
The throw is taught here bypassing the standard judo sleeve-lapel grip. Students grab both lapels, gap close by cross stepping in, and drop into a low and wide stance. If throwing the opponent with right side leading, the thrower looks to the left and uses a high left elbow. The opponent's weight is pulled onto the body, and the throw is effected with the hips shot up into the opponent and the arms pulling to rotate the opponent over the hips. The opponent is controlled into the fall and the grip is not released until after the opponent lands properly.
See the follow up to this post Taekwondo Won-hyo: Over the Shoulder Throw
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Won-hyo's Three Knifehands