These pins are a necessary addition to any industrial and scientific project... The Hillman Group 58529 4 Inch 3 Pack pins are incredibly sturdy and have not yet failed me while holding up heavy materials. The SHARPNESS of each pin allows for easy insertion into any material without causing any damage. However, the pack could offer more than just three pins. Overall, a reliable product that I would highly recommend to anyone in need of a durable pin for their projects..