Borosilicate glass 2.465" slip, 12" tall. Turns a common 20''' Matador lamp into a brilliant ''white light'' lamp by controlling the shape of the flame and the draft around the wick. I designed this chimney using the Vulcan principle patented by Emil Wild on August 19, 1884. The flame is absolutely stable even at a full curl. These chimneys require the use of a thick wick. (Limit two chimneys per order/per package.)