Holleys new GM Muscle Series air cleaner kits are the latest expansion to our officially licensed GM product line. These die-cast aluminum air cleaner kits were designed to have a no-frills, modern style with prominent raised GM "Chevrolet and Bowtie" logos. Intended as an alternative to the existing GM ZZ6 accessories, Holleys GM Muscle Series air cleaner kit can be the perfect addition to your engine bay if you are searching for a subtly custom variation from the OEM options. 14 in. round air cleaner kits are available with a premium element featuring red pre-oiled cotton gauze (washable and reusable) or a mesh-reinforced paper element â both options come in 3 and 4 inch heights. Each air cleaner kit includes a polished or black Sure-Flo base (designed for Holley 4150 and 4160 and other carburetors with 5.125 in. diameter neck) and all mounting hardware necessary for installation. All GM Muscle Series accessories are available in four custom finishes: natural cast, polished, satin black, and factory orange (all finishes have machined "Chevrolet and Bowtie" logos aside from polished version).