This is a Zebra JT woven strap, modeled after an actual real-life freaking Zebra.
Fits all Proflex, Proshield, Proteus, Vidar, nForcer and Flex 8 masks.
Combo with a frame to give your goggle a custom look:
https://paintballretro.com/search?q=proflex+frame&options%5Bprefix%5D=last