Also purpose is different between the Type 52B destroyer and the Type 54A frigate. The Type 52B is meant to be an area air defence warship, meant to project a large anti-air bubble around the ship to protect high value assets (such as a carrier), while the Type 54A is meant to be a general purpose warship, that is intended to fulfill most needs of the PLAN, such as convoy escort, and as such, their air defence capabilities is more limited because the air defence system is more limited to protecting the warship itself, and is meant for mass production to flesh out fleet numbers.