Fitting structure for tools

A fitting structure for tools comprising:

• a fitting end of a fitting tool and a fitted end of a fitted tool;
• the fitting end including a toothed retaining area formed on an inner wall thereof, a concaved portion defined on an upper end thereof, a peripheral groove arranged around the concaved portion, and a ring disposed in the peripheral groove;
• the fitted tool including a working portion arranged on a lower end thereof, a polygonal engaging portion defined over the working portion, an annular locking portion formed over the polygonal engaging portion, wherein the annular locking portion has an annular lock trough defined thereon, and the annular lock trough has a color marking element fixed therein for identifying the fitted tool;
• wherein when the fitting end of the fitting tool is connected with the fitted end of the fitted tool, the polygonal engaging portion of the fitted end retains in the toothed retaining area of the fitting end, and the annular locking portion of the fitted end is engaged in the concaved portion of the fitting end, the fitting tool is retained in the annular lock trough of the annular locking portion of the fitted tool by ways of the ring, such that the fitting end of the fitting tool is connected with the fitted end of the fitted tool securely.