The material also seems unaffected by sweat, so it doesn't get slick when wet and slip down, which was one of my fears when purchasing.

Good soft, strong, comfortable material!

This one can be fastened 2 ways and is made of superior materials than others I have purchased

Due to the phone's weight and the slick material of my jacket, the armband kept wanting to slip down, forcing me to tighten it slightly more than what was comfortable in order to keep it in place

The non-permeable material protects my phone from sweat and moisture.

Cheap materials, look somewhere else.