The Siemens SENTRON 3VA2110-5HL32-0HH0 is a 3-pole molded case circuit breaker rated for 100 A continuous current, with an adjustable thermal-magnetic trip unit covering 150 A to 1,200 A. That trip range means you can set it for a feeder or a large motor branch without swapping the breaker body — useful when the load calc lands somewhere between 150 A and the full 1,200 A ceiling. The interrupting ratings climb to 187 kA at 240 V and hold at 121 kA through 440 V, then taper to 75.6 kA at 500 V and 3.7 kA at 690 V. Power loss maxes at 10 W, so it won't cook the panel.
The 3-pole footprint is standard for a 100 A frame; you'll need about 4 inches of rail width per breaker. The shunt trip and aux switches are factory-installed, so no field wiring of add-on modules.