Silva Sizing



  1. What is magnetic North pole?
    It´s the point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards. The magnetic North pole is in continuously movement. The Magnetic North Pole is the point that traditional magnetic compasses point toward.
  2. What is the geographical North?
    “Geographical North” is also called “True North” and is the direction from any point on Earth toward North Pole.
  3. What is inclination?
    A compass will react to the Earth´s magnetic field and the compass needle will tilt (vertical direction) downward or upward depending where you are location on Earth. It means that the needle will always be parallel to the Earth´s magnetic field.


  4. What is Deviation?
    The difference between True North (geographic North) and Magnetic North.
    Magnetic deviation will occur in some places of the world, often caused by high amounts of metallic ore in the ground. This will cause the needle to divert either west or east and the deviation varies between 1 and several degrees depending on the amount of material that influence the needle at the place where you are. Most maps will have a note regarding the local magnetic deviation and on how to calibrate for it. Many of Silva’s compasses have a function to compensate for the deviation; this is very useful for avoiding mistakes.


  5. Our balancing zones
    All Silva compasses are balanced in three different zones:
    MN (Magnetic North)
    ME (Magnetic Equator)
    MS (Magnetic South)
    balancing zones
  6. Can I use my compass in any part of the world?
    No, all Silva compasses are weighed for one of three magnetic zones and using your compass in the “wrong” zone will cause the needle to tilt and may result in it getting stuck against the roof/floor of the capsule and showing an incorrect north.


  7. Does Silva make a compass that can be used all over the world?
    No, Silva Sweden does not have a compass equipped with a so called global needle.
  8. My compass has turned 180 degrees and now north is south and vice versa, can this be remedied?
    The reason that the compass is not showing north is most likely due to it being subjected to a magnetic field that has polarized the needle. This is, unfortunately, fairly common in today’s world since we carry a lot of items that emit a magnetic field such as mobile phones, GPS and other equipment. A compass needle cannot change its own polarization; it has to be "forced" to reverse its polarity by a magnetic field.

    We write in the manual that it is very important to check the compass every time it is used since polarizations does happen, it is as important as checking any part of your survival gear before it is used, since your life may very well depend on its functions.

    It is not complicated to reverse the polarization of the needle but to be 100% sure of the result you should be using a controlled magnetic field. Because of this we do not recommend that you polarize your compass by yourself.

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