I have a neoprene allergy and get hives, etc. from mask straps on my face.
PadACheeks stopped that.
Then I got a hybrid and I got a rash on the back of my neck. PadACheeks sell a fleece cover for the back of the neck strap too--I got that and it worked.
Also PadACheeks made my hybrid fit better.
Also, I got a chin rash from the hybrid's silicone chin cup. I cut a small piece of cotton gauze and folded it over and put it in the chin cup between my chin and the cup. That worked for me.