Temperature range from -8°C to -14°C (18°F to 7°F). Recommended iron temp: 150°C (311°F).The 5 series is brand new for the Cera Nova X line, and fulfill a hardness gap between the 4 and the 6 series. It’s easier to apply than the 4 series, but provides outstanding glide properties within its temperature range, and has great durability.The speed of the iron should be approx. 8-10 sec. on a skating or alpine ski.