The EN 60898 figure governs domestic and similar installations; the higher IEC 60947-2 rating applies when the breaker is used in industrial panels where the prospective fault current may be higher. That dual rating gives you flexibility on where you can spec it.
This breaker uses tunnel terminals top and bottom — spring-cage style, so you push the wire in and it clamps. Installation depth is 70 mm, which is standard for the 5SP4 family and fits most DIN-rail enclosures without crowding the backplane.