This is a set of 4 Daiwa Ika-sama Trays, size M. Used for two seasons. There is some white residue, possibly water stains, on the aluminum plates, but this does not affect use. I don't think there are any noticeable scratches or stains. Made of resin, the tray is slow to warm up once cooled, keeping squid fresh and allowing you to bring them home in good condition! ■ Resin material that is slow to warm up once cooled ■ Easy assembly and storage with slide plates ■ Water drainage structure prevents water from pooling in the tray ■ The integrated body and slide plates are removable for easy cleaning and hygiene ■ Can be used for fish such as filefish and horse mackerel, as well as squid ■ Hybrid structure with aluminum plates for rapid cooling