Jpen how to backhand punch

[PenHoldSandro]

I am a Jpen player, and I play short pips. I want to ask as to how you backhand punch properly???

 

[PenHoldSandro]

I am a Jpen player, and I play short pips. I want to ask as to how you backhand punch properly???

What is the form needed in order to perform this technique?