4500 Drop Base Air Cleaner Black w/6 Red Washable Gauze Filter 16 X 6 Black Drop-Base Air Cleaner for 4500 Series Carburetors with 7-1/4 Diameter Neck HolleyDoes your engine need Lots of fresh air? Holley is proud to offer a breath of fresh air with our new 16x6 inch drop base 4500 air cleaner assemblies and filters. Available in chrome or Edp black. The 6 inch assemblies are available with a red washable gauze element only. The tops are so large and smooth we decided to leave them plain for a nice stealth look, or to use as a canvas for creating your own look. They feature a 15 16 inch drop base.