I like this chart but still I don't know what AWG is used for 400A : r/electricians
Amazon.com: WCS Bare Copper Wire, C110, ASTM B3, MS20995CU, .0126 in (0.32 mm), 28 Gauge, Soft Temper, 1 lb (0.45 kg) Spool, approx. 1,993 ft (607 m) : Industrial & Scientific
Package Code SBC-12-250, 12 American Wire Gauge (AWG) Size and 250 Feet (ft) Length on Spool Solid Bare Copper Wire On International Wire Group, Inc. (Omega Wire, Inc.)
Artistic Wire, Copper Craft Wire 22 Gauge Thick, Bare Copper (8 Yard S — Beadaholique
Table of equivalent AWG Wire and Resistance per foot
Wire Gauge Diameter Chart | ... Download Chart of AWG sizes in metric. Gauge Number vs Wire size Table | Cable chart, Electrical circuit diagram, Electrical wiring
What is the size of a solid copper wire for a 40 amp breaker? - Quora
3-5 mm Round Copper Wires, Wire Gauge: 5-10, for Industrial