Ugears Dynamometer ★Mechanical 3D Puzzle Kit Model Toys Gift Present Birthday Xmas Christmas Kids AdultsModel Size ( Length x Width x Height ) 147 X 72 X 170mm Package Size ( Length x Width x Height ) 37 x 14 x 3cm Package Weight 350g Number of Parts 48 If you have trouble deciding what to do with your day then the Dynamometer is just the machine for you. Similar to our Pneumatic Engine, this model operates by turning air pressure into motion. The difference is that this model will give direction to your otherwise aimless day. Blow on the top gear to