How about a toe kick to the area just behind behind your ball sack.
This one hurts like hell.

If done right that's a kill point you must be able to break boards with your toe to kill with this point.
Master Moran

yes CV #1 is a toe kick striking point.
I am Now writing about Uchi Kuro Bushi point now. it is the most dangerous striking point on the body, which uses a toe kick. has anyone out there used this point or knows about it? this point make ST#9 look like childs play!

Kyushoguy,
  CV# 1( Ren#1) name is Huiyin. it is location is between the anis and the scrotum. I asked if someone out there has used it be cause like most #1 point of the meridans, there very dangerous. the Ren #1 point is a very hard to hit point unless the person being hit is very tall. and I wanted to see if anyone out there knows any thing about it. The kick is so difficult that many systems list it but don't know how to use it. So I wanted to see if any of the masters who read this site know how to use it. so far there has been no replys. I will write out the point at some point for all to read. The masters which I here from mostly never post, they e-mail instead But there is no reply at this time.