Cir-polarizing Question

When I got my camera it came with a Hoya Cir polarizing filter, on the box it says pitch 0.75. What does this mean? Please forgive me if this is a silly question I dont really know anything about this kind of filter.

Thanks in advance

It is the pitch of the screw thread where it mounts to the lens, i.e. the ditance between the peaks of the threads.