Superior Vent-Free Logs and Burners Double-Flame SeriesTHE DOUBLE FLAME Series unique, clean burning design provides 99% heating efficiency, which allows you to operate the logs vent free with the fireplace damper closed. With no venting required, there is no heat loss up the chimney. Heating vent free gas logs means youll never again be left in the cold with wet logs or without heat during a power outage. Features Available in 18 and 24sizes Two rows of dancing yellow flames Ceramic Fiber logs for a