What breaker do you with a 120amps 120volt arc welder?

For a 120-amp, 120-volt arc welder, you typically need a double-pole circuit breaker rated for at least 30 amps. This allows for the necessary current flow while providing adequate protection against overloads and short circuits. It's also important to use appropriate wiring to handle the current safely. Always consult the welder's manual and local electrical codes for specific requirements.