The main part of a darby is the base: a long, flat piece, with a smooth finish.
Lipped edges
The darby is manufactured with a slight U-shape, which gives it a lipped edge. This prevents the tool from digging into the soft material you are smoothing and removing any of the covering accidentally.
Handles
Every darby has handles, which can be one of several designs. Handles make the tool more user-friendly and easier to control.
Most common darby handles consist of two add-on pieces. Their positions are adjustable, by sliding them along the handle rail. This makes the tool even more ergonomic for comfortable use, and means the handles can easily be replaced if they wear down or break.
Alternatively, handles can consist of one long or two individual piece(s), permanently attached to the base.
Dimensions
The length of a darby is variable depending on your needs. They are generally available at between 1.2m (4ft) and 2.4m (8ft).