The zero-clearance Flex Island fireplace insert is designed as a room divider, with four open sides enabling the hypnotic flame to be viewed from the front, back, left and right sides. The UL Listed Flex Island models come with a base component that holds the burner and a top component that lines the bulkhead above. The Flex 86IL.BX2 includes a design that features Decorative Boxes on either side of the firebox. This 2 Box-design boasts an attractive visual symmetry while the glass panels that divide the Decorative Boxes and the Firebox create an uninterrupted, streamlined look. One of the most popular of the XL Series burners, the XL900 burner delivers a stunning linear flame. With a 2.4 gallons capacity, this elongated burner can heat up to 646ft2, making it ideal for larger residential and hospitality spaces such as open plan restaurants and bars or hotel lobby areas. Efficiency is a key feature of this burner, delivering up to 13 hours of heat generating flame from a single refill.