Reefer XL 300 ClearView LidThis lid will cover the original Red Sea 300 XL, ONLY and will include an overflow cutout. ClearView Lids was founded to create sleek, aesthetically pleasing, durable, alternative lid solutions for keeping your finned friends safely in your aquarium. With 3 lid styles to choose from and a wide variety of available customization options, we're certain to have the right solution to fit the individual needs, tastes, and budget of hobbyists everywhere.