A three-in-one design, comprising a ruler, a pen and a horizontal metre, satisfies various needs in three professional occasions of business meetings, offices and construction sites with all essential functions of quick magnetic lock and release, free standing and flipping. Protected with shockproof silicon at both ends, the metallic ruler is laser-engraved with six standard scales, peeling-free. The model for office use comes in a Frixion ballpen with an eraser at the LOGO side and compatible with standard ballpoint pen refills. The one for drawing comes with a built-in dust-free lead pointer for handy sharpening and storage. The pen in both types is inlaid with real Meng Zong bamboo for the beauty of nature and an anti-rolling function.