Metal-Fab Type B-Vent 4" x 48" Double Wall B-Flex Flexible Pipe Length w20 there is always a chance

there is always a chance you won't be able to run your chimney liner straight-up-and-down to your appliance

Area to left & right of lid: 3 1/4 inches

This Clean View Circulating Kit allows you to skip the traditional appearance of the slatted louvers

fireplace insert with added trim kit

Metal-Fab Type B-Vent 4" x 48" Double Wall B-Flex Flexible Pipe Length w20 there is always a chanceType B Gas Vent products are tested and listed to UL 441 for approved gas appliances and feature our innovative twist lock connection and locking tab, eliminating the need for sheet metal screws. Metal Fab Type B Gas Vent combines hemmed flues and casings that maximize product durability and reliability and minimize installation time. Designed for versatility, Metal Fab Type B Gas Vent products 3" 6" adapt to major competing brands and when installed