ABB S202MUC-K15 S200MUC MCB, 2P K 15A, 277VAC/500VDC

Trip Curve K is the key here: it allows a magnetic trip threshold of 8 to 12 times rated current, which means it holds through the inrush of motor starters, transformers, and solenoid valves without nuisance tripping. That makes this 15 A unit a fit for protecting a small motor branch circuit or an inductive load group — not a general-purpose lighting or resistive load, where Curve C or B would be the normal choice. The AC interrupting rating is 6 kA at 277 VAC; on the DC side it breaks 10 kA at 500 VDC. That DC rating is higher than many comparably sized MCBs — relevant if you are protecting a DC bus or a battery-backed control circuit in the same panel.