The 20" Classic Smoker by the Horizon Smoker Co. sets the standard for the Barbecuer who needs some more room than the 16" size offers.  For starters, the 20" diameter pipe provides much more room and the options to cook larger  size peices or meat, upright beer can chickens, turkeys, and so on.  The main chamber measures 20" by 36" and comes with a 20" by 18" firebox.  The extra space in the firebox is nive to allow larger peices of wood as well as more space for ash buildup.  As Roger Davidson told me once, "The 20 inch Classic Smoker just seems to hold heat with the ease and limited effort as though it's just the perfect size."  When you move up to the 20" Classic Smoker you get larger 16" Wagon Wheels as well as the heavier duty framed cooking grates.  Weighs in at 400 lbs. yet moves easy.  Enough room to easily cook for 70 or more people.  Well worth the upgrade in money spent from the 16" size if you may need the extra room down the road someday.  This unit will not limit you!  The 20" Classic Smoker below  shows this unit with an upgraded warming tray on the  firebox added.  You can certainly order it without and save a few bucks.