We are going high-tech with space age materials. This heavy duty survival knife features a 2.5 mm thick 12C27 sandvik blade, a thick serrated area, an integrated 4 seasons 110 db survival whistle and a shackle key. The handle features a non-slip area (colored area) and can resist extreme temperatures (-40c to + 80c). Dimensions: 7.75" x 1" x 1" (Open) Blade Material: XC90 Carbon Steel Blade Length: 3.75 inches Handle Material: Fiber-reinforced Polymer