In 1968 Heatilator had the number one best selling masonry form fireplace on the market - the Mark 123 fireplace.  At the time, these fireplaces were revolutionary in the way they helped you heat your room. And, chances are, if you have a home that was built in the 1970s and you haven't remodeled, then you probably have an old Mark Series Heatilator fireplace in your den, living room, or family room. We'll show you how to update that 1970's look in no time!