The Magnums were made in 2 sizes and also an early and improved version. These in the pics are the improved.
They are made of stainless steel and the edges were hollow ground. A very, very good broadhead.
They are out of production. They can be a budder to sharpen because of the bleeder in the way, but when you get them sharp it is a high preformer!
The improved version are quite common. The early version is not rare it is just harder to find because the differences between the early & improved are subtle.
Some hunters have been known to snap the bleeders off the large model and they then have a 1 1/2" wide 100gr head!
I still have 10 of the wide models new, never used.