The tonfa (Okinawan: トンファー tonfā, Malay: topang, Chinese: 柺; pinyin: guǎi) also known as tong fa or tuifa, is a melee weapon best known for its role in the armed component of Okinawan martial arts. It consists of a stick with a perpendicular handle attached a third of the way down the length of the stick, and is about 15–20 inches (380–510 mm) long. It was traditionally made from red or white oak and wielded in pairs. The tonfa is believed to have originated in either China or Southeast Asia where it is used in the respective fighting styles. A similar weapon called the Mai sok san is used in Krabi-krabong and tomoi.
Although the tonfa is most commonly associated with the Okinawan martial arts, its origin is heavily debated. One of the most commonly cited origins is China, although origins from Indonesia to Thailand are also possible. Okinawan tradition derives the tonfa from a millstone handle. The Chinese and Malay words for the weapon (guai and topang respectively) literally mean crutch, which may suggest the weapon originating from the crutch. In Cambodia and Thailand a similar weapon is used consisting of a pair of short clubs tied onto the forearms, known in Thai as mai sok and in Khmer as bokgatau. In Thailand and Malaysia the mai sok often has a similar design to the tonfa, with a perpendicular handle rather than being tied on. This weapon might be the original version of the tonfa.
The tonfa measures about three centimeters past the elbow when gripped. There are three grips, honte-mochi (natural), gyakute-mochi (reverse) and tokushu-mochi (special). The starting grip, honte-mochi, places the handle in the hand with the long arm resting along the bottom of the forearm. This grip provides protection or brace along one's forearms, and also provides reinforcement for uraken (back fist), hiji waza (elbow techniques) and punches. In use, the tonfa can swing out to the gyakute grip for a strike or thrust. Martial artists may also flip the tonfa and grab it by the shaft, called tokushu-mochi. This allows use of the handle as a hook in combat, similar to the kama (sickle). This grip is uncommon but is used in the kata Yaraguwa.