compass usage:

the compass must be placed horizontally. At the same time, to avoid confusion in magnetic needle, keep a certain distance from objects containing magnetism. The specific methods are as follows:
1. More than 10 meters away from the barbed wire;
2. It is more than 55 meters away from the high voltage line;
3. More than 20 meters away from cars or planes;
4. It is more than 10 meters away from objects containing strong magnetism, such as various magnets and external magnetic speakers;
5. Objects with weak magnetism, such as magnetic snaps, are more than 0.5 meters away.

Note:
1. Use it in a horizontal state to ensure accuracy as much as possible;
2. To avoid confusion in magnetic needle, please keep a certain distance from barbed wire and magnetic objects when using;
3. It is not possible to tap objects with a mapping ruler to avoid affecting the measurement accuracy;
4. Keep the plate surface and lens bright and clean, and do not wipe them with dirty cloth or hands;
5. Close when not in use, and place it not close to ferromagnetic materials to avoid loss of magnetism.