It isn't Kevlar, but it is a ballistic plate. That company makes them to go inside of walls and podiums and desks and things like that. It's actually woven fiberglass/resin.
Their site says it can be cut with a 7" diamond circular saw blade. For small openings like for electrical outlets and the like they suggest a diamond grit wheel like you cut ceramic tile with.
Level 3 plate like that is tested and can withstand rifle fire from a .308 win., as well as stopping .44 mag as mentioned above.