These hinged fluoride trays are an excellent way to dispense fluoride treatments with upper and lower arches attached together. The tray is made of closed cell, 4 lb. density foam for good rigidity. With excellent anatomical depth for gingival line, the tray promotes full coverage of the fluoride applications. Features: – Sizes: Large, Medium, Small/Medium, Small – Sizes are color coded with four different colors representing four sizes – Placement handle for easy insertion – Available in 100 in a bag