The blades are cut and intended for use specifically with the "Seven" handle ONLY. Options include all of our single-durometer blades. These are too long to work with a tintingruven handle or other 5 inch handle. These are also too short to fit in an 8 inch handle. Sledgehammer (Yellow): 93 durometer – Designed for maximum solution extraction, this blade is perfect for the final pass after film installation. De-Hydra (White): 90 durometer – A versatile, medium-hardness blade that excels at solution extraction, and is our best-seller. Cyclone (Red): 87 durometer – A middle-ground hardness blade ideal for super-curved surfaces, such as windshields and backglasses, for effective solution extraction. Riddler (Green): 83 durometer – Slightly firmer than the Judge, the Riddler is perfect for glass prep to clean and prepare the surface before applying window film. Judge (Orange): 79 durometer – The softest blade specifically designed for prep work, offering the necessary drag to effectively remove contaminants from the glass.