Below is a list of Magnetic Shields manufacturers from Ayer, Massachusetts. Magnetic shields are materials or products that protect electronic devices from interference from magnetic fields or electromagnetic fields (EMF). Since magnetic fields may only be redirected, the magnetic shields serve to block or absorb the electromagnetic interference (EMI) rather than removing or destroying it. In addition, there is no known material that is able to block a magnetic field without being attracted to the field itself. As a result, only materials with high magnetic permeability, meaning that they are highly attractive to the magnetic field, can be used.