Use only the most trusted T-squares for your drafting tasks. Choose from our selection of professional grade T-squares by Alumicolor. These precision tools have been a best seller in school and office supply stores for over 35 years. Alumicolor’s T-squares are made with 1 1/2” tempered aluminum shafts and shatter-proof ABS plastic heads. Photo-anodized calibrations are guaranteed not to fade or rub off over time. Choose from lengths of 12, 15, 18, 24, 30, 36, 42, and 48 inches, all calibrated with both centimeters and inches.