Name of a part

Hi, I'm trying to figure out the name of the part I'm trying to replace. I had to take apart my transmission to replace the clutch plate. I put everything back together. The problem I'm facing is I don't know the name of the part that covers the axle seal. Before you put the axle back in. It's like a plate with 4 bolts. The reason I'm wanting to know the name of the part is so I can replace it because it is leaking transmission fluid. I think the seal is no good also I need to replace that part. But don't know its name, lol. Please let me know what it is called. Thanks!