Hiraken uchi

Hiraken-uchi (literally: "leopard-fist strike"), is a more robust variation of the four-fingered spearhand strike. Hiraken uchi is thrown just like a front-foot or reverse punch, but impact is made with the second knuckles instead of the seiken.

[Photo of a hiraken from the front and side] 

Hiraken uchi is used to attack soft tissues, such as the opponent's throat, solar plexus, abdomen, bladder, or armpits.

[video of a hiraken from the front and the side]

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