My stockers had a steel braid surrounding the rubber. It was definitly steel as it shot sparks when I cut through it (cutting wheel).

Maybe Mazda switched to cloth braid after the early '86s?

 

Aaron I can't believe how confusing this got! I do recall having to use a pair of diagonals to cut mine of of my 87. Most people look at them and they are fabric on the outside, but there is a metal reinforcment it the center of the rubber wall.
I almost want to hit the bone yard and cut one to bust the myth!LOL

 

The one in my jpgs is a series four and has no metal in it except the end fittings. Want me to stand the thing on its edge so you can see? That hose came off the hose that feeds the rear housing. You know, the one with the the Metal piping in the middle. It is as stock as stock can get.