Student Math Geometry Kit: This compass holder is compatible with any standard-sized pencil or pen. The ruler, set square, and protractor all have graduations for easy identification. Lock-in Adjustable Metal Compass: Tired of misaligning and breaking lines when drawing large circles? This compass with a knob-locking mechanism securely holds the set radius. The needle tip is non-slip and won't slip, making drawing perfect circles and arcs smoother and more stable. Comfortable Grip: The ergonomically designed compass head provides a comfortable grip. The universal compass holder is compatible with any standard-sized pencil or pen. The ruler, set square, and protractor all have graduations for easy identification. The geometry tool kit includes: 1 metal study compass, 2 set squares (45° and 30°/60°), 1 ruler, 1 protractor, a compass-specific pencil, a pencil sharpener, and pencil lead. It also comes with a portable storage case. Transparent Storage Case: Always rummaging through your bag for scattered drawing tools before exams? This transparent hard case with clips securely holds each accessory in place. The clasps are firmly secured, preventing items from shifting or falling out of your backpack, and making it easy to see what you need.