This Brass Ruler Position Block with 300mm Steel Ruler is used for length and width measures. The stainless steel ruler has high precision and high efficiency, with metric and imperial dual scales on both sides. The brass positioning block slider can be moved to the required position to mark lines, easy to user. The brass positioning block is suitable for all kinds of steel rulers, with high precision, and the ruler is not easy to fall off. With our MG22 you can convert any steel ruler into a precision marking tool.