Costco's Ahi Tuna Saku Block is a premium, sashimi-grade yellowfin tuna product sourced from the Philippines and sold by the pound at the service deli counter. "Saku" refers to a precisely cut, rectangular block of skinless, boneless tuna loin that is trimmed to a uniform shape, making it ideal for slicing into sashimi, searing as ahi steaks, or using in poke bowls and other raw fish preparations.

The saku block format delivers restaurant-quality tuna with minimal preparation required. Its deep red color, firm texture, and clean flavor profile make it a favorite for home sushi and sashimi enthusiasts. The product is sold fresh and priced per pound, with each package weight varying at the deli counter.