The latest Tracer Unit from JG. It is all metal and is a more compact and user friendly design. Just like the original, the newer model uses 4 AAA batteries housed in the interior covered by the aluminum case. The direct screw on threading is now metal is a 14mm counter clockwise thread, so it fits most airsoft guns. The simple push On/Off Switch is located just under the threading and makes it much easier to manipulate as well as preventing the tip of your tracer to fall off when trying to turn it off or on.