Product Name: Science and Technology Small Production: Earthquake Alarm
Weight: about 55g
Dimensions: 8*6*12.5cm
Packing: opp self-sealing bag
General knowledge of seismograph: In 132 AD, Zhang...
Principle of gear shuttle: Chemical energy in the battery is converted into kinetic energy of the motor. The motor drives the driving gear to rotate. When the driving gear touches the ground,...
Small Fabrication Kit: Optical Fiber Lamp Do you know what optical fiber lamp is? Fiber-optic lamps and lanterns are energy-saving, artistic shape of the new type of lamps. It integrates high...