Since they must withstand powerful strikes, most nunchaku are made from oak, although ebony and ironwood are used because of their weight. The connecting cord is usually made of silk or nylon but chain is also used.
The proper length of each stick should normally be equal the distance from the middle of the hand to the elbow so a stick may be with the length along the forearm as protection for blocking.
A hard plastic version of the nunchaku made by Monadnock and Orcutt is used by some law enforcement agencies in the United States. Some law enforcement agencies experimented with it during the 1970s but abandoned it. They found that officers needed extensive training to be effective with it, there were too many training injuries, it was cumbersome to carry, and the public perception was that it was a weapon designed to beat down suspects. Some law enforcement agencies still use the nunchaku, such as taught by Orcutt Police Defensive Systems.
A street version of the nunchaku is shown below. The two halves may be screwed together so they appear to be a short baton. Many states, particularly California, specifically list the nunchaku as a deadly weapon that cannot be carried in public. Since they are large and awkward to carry, they are not effective as a present day self-defense weapon. Also, if used, even in a self-defense situation, you will probably be viewed as the "bad" guy.