The butterfly knives are especially popular in Wing Chun and are mainly used in Southern Kung fu.
The double hook (or tiger hook) swords are typically used in Northern styles of Kung fu. They are similar to swords, with a hook at the end, and a guard similar to that of the butterfly knives. Tiger hooks can be used for close and medium-range combat and can be used for long-distance combat when both weapons are hooked together.
