You want a stable and rugged fulcrum platform when you do your meter stick lever experiments. This is the one you want! Its cast aluminum construction is so durable it will not spring out of shape during use. Its wide base (3" x 3") and tall arch (7.5") make it perfect for teenage hands trying to make things balance. The smooth notched top is matched perfectly to accommodate a knife-edge clamp for smooth operation. Meter stick and knife-edge clamp (AP4672) sold separately.