Item Type: Experimental Kit Material: Plastic Color: As shown in the picture Assembly Size: Approx. 18.5x17x8cm / 7.3x6.7x3.1in Weight: Approx.115g/4.1oz Applicable Age: Over 5 years old Ability Development: Intellectual development Experiment Type: Physics Package List 2 x Base 2 x Conveyor Belt 2 x Connecting Rod 4 x Half Moon 2 x Backlight Hemisphere 2 x Long Axle 2 x Short Axle 2 x Belt Pulley 2 x Paperboard 1. Please allow 1& 8209;2in error due to manual measurement. Thanks for your understanding.2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. 1Children can learn some scientific knowledge while playing, expand scientific knowledge and promote children's intellectual development. 2It can cultivate children's operation ability and logical theories through disassembly and assembly. 3It can also help them think, increase creativity and interest in learning, handeye coordination and concentration. 4Made of high quality plastic material, safe, nontoxic, and comfortable without worrying about scratches. 5Can be used as an educational and experimental tool in the classroom to enhance fun. A great gift for children.