- Drawing ruler - t - square
- Ustable head t - square
- Cad have already replaced the t - square and drawing board and become to design the main tool of the personnel along with the cad technique development , and consumedly lower the labor strength of the design personnel , and increase the work efficiency of the design personnel
A T-square is a technical drawing instrument used by draftsmen primarily as a guide for drawing horizontal lines on a drafting table. It may also guide a set square to draw vertical or diagonal lines.