1. MN was used for the inverse magnetic polarity device that is no longer used due to adverse effects in many people. It is suggested that we no longer use this Boost output, although it is still placed for longer-term users who still have the devices and choose to use it.
I couldn't ever use the MN polarity, so for me, it is a total "Do Not Use."
2. Apparently Killing effects on MN port is stronger but should not be used long term (example 4+ days in a row)
I alternate between BN and MN usage and I can't tell which one is more effective as it both seems to work.
3. MN = magnetic north BN = bio north. In only rare instances is MN used. 99% of the time you want BN to be the one to use.
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