Empire E-Vent, Avatar Lockout Tabs Standard

These work great to minimize vertical movement of the mask. If you lose 1 its not too bad. If both are gone the mask strap can stay in place on the back of the head, but the mask itself can rotate upward during heavy movements (diving, running, sliding in some cases). Definitely a must with the Empire E series masks. Also a downside to the mask itself because of the rotation issues listed above. 5 stars for the specific product and its function, durability, ease of use and designed purpose.