i am not sure what size relay to get for this.. just a regular 30/40a relay from the auto parts store?

i am still learning about this stuff but i really appreciate all the advice from all of ya's

__________________
Vehicle A - Kenwood eXcelon KDC-X979 HU; Kenwood eXcelon 5.25 components in q-forms; Rockford Punch 75.2; Kenwood eXcelon KAC-X810D; American Accessories 1.2f capacitor; 1 Pioneer Premier TS-W2000SPL in a Bass Slammer box @ 38Hz

Vehicle B (daily driver budget system) - Alpine CDA-9830 HU; Rockford Fanatic X 6.5 components; Pioneer GM-H200; (2) Kaption COMP-108 10's wired to 4ohm in a Kaption factory box tuned to 35Hz; Audiocontrol 2xs (only deck installed so far on this one i'm getting started soon)