This is a method that comes out of Uechi-Ryu or Pangainoon Sanseiru Kata. The hand positions are in other Kata and Styles as well in various sections, the action is you parry and dig right in with the fingertips to the arms, body or neck. They call the hand tool Kakushiken, we know it as the Blood Pool Hand from the ancient Bubishi. With the parry and the grab, the grabbing could be into the the tissues of the arm, the muscles, the vascular tissues, the nerves, or you could be grabbing in that way you could also into the throat with a thumb just coming right across or behind the windpipe, and stretching the neck out so you can get into the Subclavian Artery.
There are also nerves such as the Brachial Plexus as well as many other targets you could be attacking. In the extended version, we're going to show you an attack on the subclavian and the nerve tissues with both action (that's basically what the Uechi practitioners think of and use) and it's great technique, but there are other ways to apply that action.
As you're coming in with it in Sanseiru, you're going to also notice is that it comes in with body weight. Once that body weight comes in and you drop that that action as well using this technique more as a gripping and pulling action. Now once that weight drops, you have already dug your fingers in, so instead of like pecking down like a Crane attack, (now that's what most Uechi practitioners utilize, is Crane attack for the most most part, they do use a little bit of Tiger, but mostly just the Crane, where they're striking and using that as a striking type action