Toy material: PlasticApplicable age :6+[Product Name] Scientific Microscope Set【 Product Packaging 】 Color Box (36*26*11.5)Multiple combination multiplier to meet different needs (200X/600X/1200X)Two...
Transmitter course courseware The principle of radio receiving and transmitting is that the transmitter sends out current of different frequency and wavelength according to the requirements of...
Objective course: learning physical circuit diagram Double control switch: it can have two switches to control lamps and other electrical appliances For example, turn on the switch downstairs...