That means it's sized for general-purpose protection on industrial and commercial lighting, small motor, and distribution circuits where inrush currents — like those from fluorescent ballasts or small transformers — would nuisance-trip a B-curve breaker. The C-curve holds through 5–10× rated current before instant tripping, so it's the standard pick for mixed resistive-inductive loads in a panel. Mount in any position; quick-assembly fastening snaps onto standard DIN rail.
Rated current derates with ambient temperature: 16 A at 35 °C, 14.83 A at 40 °C, down to 12.86 A at 55 °C. Dimensions: 54 mm wide (3 modular units), 90 mm tall, 76 mm deep, with an installation depth of 70 mm behind the panel face. It's IP20 with conductors connected — fine for a dry indoor cabinet, not for washdown zones.