The appearance of torque screwdrivers varies according to whether the screwdriver is electric, cordless, pneumatic or manual, as well as manufacturer preference. Manual torque screwdrivers generally resemble regular screwdrivers, although the shaft is often shorter than a regular screwdriver, and the handle is thicker. Electric torque screwdrivers usually have a handle that resembles that of a power drill, as do pneumatic torque screwdrivers. Some torque screwdrivers come with a set of bits to fit a variety of screws.
You can set a torque screwdriver to a certain amount of force, and when that limit has been reached, certain models of the screwdriver will just spin in place without continuing to turn the screws tighter, while others will alert you with a "click" when you reach the set torque. The advantages to putting screws into place with a specified amount of twist/torque is that you don't break off any components; if you're building a structure with many people, the uniform pressure gives stronger results.