Crutchfield CK1 1/0-gauge amplifier wiring kit — includes power wiring only at Crutchfield
4 gauge, 2 gauge, 8 gauge, 0 gauge...What's right size power and ground wire for your amp? - Car Stereo Reviews & News + Tuning, Wiring, How to Guide's
The Complete Advanced: 2/0 AWG Stage 2 Wiring Kit - GP Car Audio
Why are amp wiring gauge recommendations so high? : r/CarAV