From The Martial Arts Encyclopedia

The Figure 4 lock refers to any type of grappling hold that resembles a figure-four formation with the legs or arms when applied.

Most commonly seen as a Double Wrist Lock, a Triangle, or a Rear Naked Choke, figure 4 type locks are commonly seen in any grappling art.

A kimura, a type of Double Wrist Lock.

http://gnarlmaster.tripod.com/gnarlmaster/Doublewristlock.htm http://en.wikipedia.org/wiki/Triangle_choke

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