The Tunkwa (トンファー) is more known by its chinese name Tonfa.
The Tonfa is still used by numerous police forces around the World.
Tunkuwa was originaly handle of a millstone used for grinding grain. Tonfa is manufactured in red oak and its size dépends of forearm length.
Tonfa allows powerful blocks and counter-attacks. It is great complement to Karate-Do by improving punch techniques and strength.
Katas (カタ) :
Tunkawa Kihin Ichi
Matayoshi no Tunkuwa dai ichi
Matayoshi no Tunkuwa dai ni
Here is below the basic Tonfa kata Tunkwa Dai Ichi (Koburyu):