Frosts 7158 PG boning knife Progrip The Progrip models feature a dual-molded rubber handle with an etched texture, making them particularly suitable for wet conditions. The polypropylene core is surrounded by a layer of thermoplastic rubber, which significantly increases the handle’s grip and makes it more comfortable to use, providing a warm and soft feel. All blades are made from high-quality stainless steel (12C27) that can be sharpened to an extremely fine edge. Blade length:  157 mm