Both types are 50 mm long, 12 mm wide and rounded at the ends with a radius of 25.4 mm. rounded at the ends. They each consist of three layers with a total thickness of 0.15 mm. The middle layer (0.05 mm) consists of a magnetically soft Ni-Fe alloy with high relative permeability. permeability. The outer layers (0.05 mm) consist of non-magnetizable material. A special feature of these test bodies is that the middle layer parallel to the long side has slots of 42 mm length, which are evenly distributed over the width. They run through the entire cross section, but have different widths.

Castrol strips (also known as magnetic flux indicators) are used during non-destructive testing (NDT), particularly in magnetic powder testing (MPI).

They are primarily used to:

• Verify the magnetic field: Check whether the induced magnetic field is strong enough to detect flaws or cracks in the material.

• Determine direction: Reveal which direction the magnetic field is going so you can orient the equipment correctly.

• Ensure test quality: Confirm that lighting conditions, magnetic field strength and magnetic powder work optimally together.