They were usually a short 25 cm rod with a slight enlargement at one end as well as a roughened hand grip at the other. It weighed and balanced like a fighting dagger with most Romulan citizens having some form of training with this weapon. They were used extensively in physical training and combat exercises.
To use them, a knob below the handgrip was turned to one of two active positions. The first position was the tip setting which only energized as well as enlarged the end so that the stick may be used to simulate fighting with a thrusting weapon. The second positional setting energized the whole stick from the handgrip forward. By simple contact with this part, an opponent was given a mild stun shock and should contact be solid enough then a larger jolt was transmitted.
A longer version was also available which was used like a sword but was not widely used as this knife sized model. The larger variant was similar to its smaller cousin but consisted of a longer shaft. (FASA RPG module: The Romulans)