Magnetic field viewing film 
used to show stationary or (less often) slowly-changing magnetic fields; it shows their location and direction.
It is a translucent thin flexible sheet, coated with micro-capsules containing nickel flakes suspended in oil.
Available as 12" x 12", 6" x 6", or a 1" x 36" strip perfect for use with our Eddy Current Tubes.
Customized Logo are available