This kit includes 8 or 15 feet of high temperature silicone permeated door gasket material and a tube of high temperature silicone for gluing it in place. This gasket is coated with silicone, so it does not absorb creosote and harden prematurely. Kit works on any Heatmaster outdoor wood boiler and on many other brands as well. For information on how to change a door gasket, please visit this page: https://www.pineviewwoodstoves.com/single-post/2017/01/25/Fire-Box-Door-Gasket