This is a Havalon known as the Talon Fish 5" Fillet Blade 3-P, model HSC5XT3F.
5" Talon fillet blades are made of AUS-8 Stainless Steel and are honed to the same surgical sharpness found on all other Havalon Blades. Fits on all Talon handles.
Features:
3 - 5 stainless steel fillet blades