The EN figure governs domestic-type installations; the IEC figure applies when the device is used in an industrial distribution board with higher prospective fault current.
Depth is 77 mm, installation depth 70 mm — verify the gland plate clearance if retrofitting into a shallow enclosure. Supply can enter from either top or bottom. The design is short-time delayed G (residual current) and super resistant K (overcurrent) — meaning the RCD element tolerates brief surge currents without nuisance tripping, useful on circuits with electronic loads or inrush.
Thermal derating
Rated current is 16 A at 30 °C ambient. Derate linearly: 15.2 A at 40 °C, 14.88 A at 45 °C, 14.4 A at 50 °C, 13.92 A at 55 °C, 13.6 A at 60 °C, 12.96 A at 65 °C, and 12.32 A at 70 °C. If the panel internal temperature runs above 30 °C — common in a crowded enclosure — size the upstream protective device accordingly.