Bui Jung Choih - one arm extended, other hand with palm facing out. Used mostly from Ma Bouh or Gung Sik. Biu is to 'thrust', so this technique can be done to short-range closeline someone or can be used to stike with the fist. Someone also mentioned about it going 'around'. It does that too. This technique is much faster than the previously mentioned one. It is often preceeded by Pek Choih. Good for close range, but not so good once a grab has been established. This techniques power is in the torqueing of the waist (what clf is all about) and is great to help you 'break' out of trapping range back to punching range. I could write two pages on both these techniques, but I'm trying to be brief and to the point.
So there are a few different ways to do this particular Jung. The first one has virtually no variation.