Wards Essentials Trebuchet Kit, Material: High quality precision-cut Birch verner pure bond plywood, Designed to be safe and robust, Dry firings and heavy projectiles are no problem, Holes are pre drilled, Medieval weapons, engineering, and physics, Beam arm: 21in
Wards Essentials Trigonometry Puzzle Set, High quality precision-cut Birch verner pure bond plywood, Contains: Step-by-step educational guide, Includes the unit circle, three 30-60-90 triangles, two 45-45-90 triangles, two circular sectors, Kepler's triangle