The "Classic" single onigiri musubi mold is made of commercial quality stainless steel for durability and strength. The mold and press is welded on for durability. It provides and open design for fast formation of the onigiri. Stainless steel material provides non-stick qualities. No more worrying about breaking acrylic makers due to rough use, dropping or when washing or pressing. The Classic Onigiri single musubi mold is idea for restaurants, high volume operations and homes that demand durability and desire ultra high quality kitchen tools that will last. Its open design design with a separate rice press is similar to making rectangle musubi. fill with rice, press then add middle filling and add more rice then press flat again. approximately 1.875 inches deep and 3.25 inches high from base to center peak..