Welcome to the New “Polar Array” Barbecue Grill, Smoker, and Pit Air Vent Control Damper by River Country. The Polar Array is by far one of the easiest to install and use barbecue grill, smoker or pit air damper vent system on the market. The patented design allows for easy installation using only a 3/8” and a 1/2” drill bit. No more trying to cut of triangles or large circles using a saw. The Polar Array features a unique compression spring mounting system for secure mounting and easy adjustment of the air flow. The Array’s works great for adjusting either air intake or air/smoke exhaust or can be installed in sets to control both. The Polar Array is made from heavy duty 1/8” thick steel to withstand years of use and can be painted to match your grill, smoker or pit. The Arrays are manufactured with all American made parts and are assembled right in our warehouse in the heart of the Minnesota Iron Ore Country. The Polar Array’s are available is two versions, 4” and 6”. The 4” Array is a 4” diameter flat plate with 7—1/2” Vents and is perfect for smaller backyard kettle type grills. The 6” Array is a 6” diameter flat plate with 12—1/2” Vents and is ideal for larger barrel grills and smokers. Complete mounting instructions and hardware is included. Standard Features: River Country patented Circle Air Design Easy to drill 3/8” center mount and 1/2” Array Vent Holes Compression spring mounting for easy air flow adjustment Works great for both intake or exhaust air flow Easily paint to match you grill, smoker or pit Proudly made in USA 6” Polar Array Features: 6” Diameter flat steel with 12—1/2” Vent Holes