Standard/safety classification: EN ISO 20345: S3 SRC CI The Sievi Spike pin mechanism and other safety features such as steel toe and nail protection make these a safe choice for slippery and demanding work conditions in winter. The completely renewed and patented Sievi Spike spike mechanism integrated into the sole structure of the safety shoe offers secure grip in challenging conditions. A new type of technology allows the studs to be turned in and out without taking off the shoes. The surface material of the safety ankle boots uses, among other things, water and dirt-repellent PU leather, which withstands hard use, and the warm lining keeps the feet warm throughout. The base can withstand heat up to 120 degrees. Memory foam ankle protectors are shaped individually to the wearer's foot and offer support and protection for the ankles. The safety shoes have Sievi Dual Comfort insoles, which have a PORON® shock-absorbing cushion in the heel part and the toe, which absorbs external shocks and strain even more.