Fits my large Speed and Strength jacket even though it's quite a bit thicker and wider than the factory Vault armor. I bought the elbow armor as well, and that almost didn't fit into the armor pockets but I got it to settle in. I highly recommend replacing your pants and jacket armor unless it comes with D30 level 1 or better because most armor that comes with your gear is flimsy garbage. The level 2 armor feels great in my jacket and I hope I never need to prove D30's effectiveness during a crash.