AR550 is 10% stronger/harder than AR500 Steel, based on the Brinell Hardness ratings.  All of our armor is tested to stop the threats listed above. NIJ Rating of level III is only rated to stop a .308; however, our armor will stop additional threats like the green-tipped AR15 rounds.  

"Full coating build-up" Since day 1, back in 2012, we've always sold our plates with a 1/4" build-up of polyurea coating.  Anything less results in shrapnel that could be deadly.  We only sell the best.