Front double door weather sealing

My front door lets in a lot of light and air. I have tried a couple of weatherstrips, but none of them fit the slot in the door. They are double doors, the door that locks in place has an extra black attachment (guessing it is called an astragal) that has a T shaped slot for the weatherstrip to insert into. The picture with the piece I am holding is what I am trying to replace, preferably with something that will actually create a seal because this one wasn't doing much of anything