Individual removable/washable trays that hold substrate for the?ReptiBreeze?and?ReptiBreeze LED Deluxe?Screen Enclosures. Available in multiple sizes. Small (38x38cm) is compatible with NT-10, NT-11 and NT-15; Medium (45x45cm) is compatible with NT-12 and Large (60x60cm) is compatible with NT-13 and NT-17.