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!