Allows for the construction of 12 different models. 3 to 4 models can be made at once. Gears include simple ratios – 8 16 and 24 teeth.Each square piece measures 7.5 x 7.5cm. The set contains: 4 Baseboards 6 Small gears 6 Medium gears 6 Large Gears 8 Small pulleys 4 Medium Pulleys 2 ‘O’ Rings 410mm 2 Handles 2 x 80mm struts 3 x 90mm struts 8 180mm Struts 1 x 200mm Struts 3 x 330mm Struts 18 Stub Axles 8 Stub Axle Connectors 12 Squares 22 Squared with circular strut hole 10 Squared with strut hole 40 Frameworks Squared 20 Double Frameworks Squares 14 Frameworks Rectangles 24 Frameworks Right Angle Triangles 8 Frameworks Equilateral Triangles 4 Octagon with cut-outs 1 2m Long Cord 1 2m long cord with clip 1 x 3 Hole Linkage 4 x 7 Hole linkage 8 Cams & Work Cards. Age: 9+.