Hi
I agree with mcfly5, I have checked the Quick Specs for your ML350p server and confirmed that this HP 5U 6 Large Form Factor (LFF) Hot Plug Drive Cage Kit is compatible.
If you have additional questions, I recommend reaching out to a Solutions Architect. I am happy to make that connection for you. I sent you a private message in case you would like to proceed in that direction.
Please do not hesitate to let me know any other assistance I can offer.