Materials: acrylic Size: 15 cm / 5.9", 20 cm / 7.87", and 30 cm / 11.81" Color: as shown 【VIBRANT STUDY AID】Designed for high school students tackling geometry homework at their study desks, this high-transparency acrylic block ruler makes aligning lines easy while keeping textbook text visible beneath its clear body. 【RAINBOW GRADIENT DESIGN】Bring inspiration to your creative journaling routine with a stunning rainbow gradient color transition that shifts beautifully under light, adding a touch of artistic flair to school bags and office desks alike. 【VERSATILE MEASUREMENT SIZES】Available in convenient lengths of 15 cm / 5.9", 20 cm / 7.87", and 30 cm / 11.81", this acrylic measuring tool fits perfectly in standard pencil cases or drafting bags for precise on-the-go line drawing. 【STABLE BLOCK STRUCTURE】Featuring a thick solid block shape with 1cm of depth, this heavy-weight acrylic straightedge stays firmly in place on your paper, preventing slipping and sliding during crucial math examinations. 【CLEAR GRADUATION MARKINGS】Engineered with high-contrast millimeter engraving scales, this acrylic drawing tool ensures effortless readability and high precision, allowing you to measure and trace straight lines with absolute confidence. Package list: 1x Ruler