The newest innovation in Vent Free gas logs is the G19 burner system. This clean burning system provides a dazzling flame pattern and offers two distinctive style of logs. The uniquely designed front log glows like a real wood fire and the glowing embers enhance the beauty and realism of this system. The G19 Series is available for Natural or Propane gas in 18″/20″, 24″ and 30″ sets, with variable BTU ratings from 22,000 to 40,000. Lava granules are included with the unit. Minimum Fireplace Dimensions: 18" - 24FW x 22RW x 14D x 16H (30,000 BTUs) 24" - 30FW x 24RW x 14D x 16H (40,000 BTUs) 30" - 34FW x 26RW x 14D x 16H (40,000 BTUs) Control Options: On/Off Remote with standing pilot (-12) Variable flame height remote with standing pilot (-15) Variable flame height remote control with electronic ignition (-01V)