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Mobile SIM card holder usually refers to the card slot or card holder that holds the SIM card. The SIM card tray is located on the side or top of the phone and is used to insert the SIM card to connect to the mobile network.

Plastic bottle caps are a common packaging material used to close the openings of bottles or containers and protect liquid or solid substances from external pollution or leakage.

Gas stove accessories refer to accessories or parts used for gas stoves to install, maintain or improve the function and performance of gas stoves. These accessories usually include various parts

A gear is a mechanical transmission element, usually composed of a disk or cylinder with a rack, which is used to transmit power and movement. The gear transmits power from one shaft to another through the meshing between the teeth

The O-ring is a rubber ring with a round interface shape, which is the most widely used seal in hydraulic and pneumatics. The O-shaped sealing ring is a two-way sealing element.

Magnetic materials are a kind of substances that can generate and be affected by magnetic fields. These materials are usually composed of iron, nickel, cobalt and other metals and their alloys