The Siemens 5SL6206-6 is a 2-pole SENTRON miniature circuit breaker with a B-curve trip characteristic, rated 6 A at 400 V AC and a 6 kA breaking capacity per EN 60898 and IEC 60947-2. Degree of pollution 2 and overvoltage category III cover standard indoor panel environments.
If your panel called for a C-curve — say, for motor or compressor starts — the nearest peer in the same SENTRON family is the 5SL6220-7, which shares the same 2-pole footprint, 6 kA breaking capacity, and 36 mm width, but switches to a C-curve and carries a 20 A rating at a higher power loss per pole (2.2 W vs 0.9 W). The B-curve on this part gives you faster tripping on moderate overloads, so it pairs well with sensitive electronics or long cable runs where inrush is low.