The DX481 is the kit, it contains the battery and cable. The T954J is just the replacement controller card. Let me know if this helps.
I have a call here in NY for a R710 that requires a new perc card. The part number it has currently is T954J, I have a part number DX481 here, I just wanted to know if this part will work on this box. It will save me a 6 Hr drive so... I hope so :D EDIT:  The only difference I see on the dell accessories website is DX481   T954J  So is it one card comes with the battery and cable?
Unsure of dell part number