Lake 111 Zytel 7255Z31 Inch Drop Point Blade. This is the Columbia River Lake 111 Zytel 7255Z. This knife features a 3.125”drop point blade made from 8Cr13 stainless steel and enjoys a Rockwell hardness of 55-57. This particular style of blade has a satin brush finish and a flat grind. This makes it very strong and able to withstand the toughest jobs thrown at it.