It is a very strong blade (2.5 mm thick) is serrated over 3.5 cm to cut natural or synthetic ropes and has a shackle key for 4 to 10 mm shackles. Its handle is water-resistant and whitstands extreme temperatures. It is equipped with a whistle.Features Sandvik 12C27 modified stainless steel bladeHandle - Fiberglass-reinforced polyamide withstands shocks, humidity, and extreme temperaturesPealess survival whistle functions in all weathers (110 decibels)Virobloc safety ring - locks blade in open or closed positionsBlade length - 8.5cm