At DC it still holds 15 kA per the same standard, and under UL 1077 / CSA C22.2 No.235 it's rated 5 kA — so it's accepted in North American supplementary protection roles too. The 0.3 A rating is temperature-sensitive: at 45 °C it holds 0.3 A, at 50 °C it derates to 0.29 A, and at 55 °C to 0.28 A. The operating range spans -40 °C to 75 °C, so it's fine for unheated enclosures or outdoor cabinets as long as the humidity stays within the stated curve (95% up to 55 °C, tapering to 35% at 75 °C).
Mounts in any position, and the quick-assembly system snaps onto the rail without tools.