Ramair universal filters are designed and manufactured for a very diverse range of applications. These filters themselves are constructed using stainless steel cage internal and a twin layer foam. They have an rubber polymer neck and a cone shaped filter element. These filters are cone shaped because it enables easy fitting to space restricted engine compartments and with the extremely large amount of foam surface area an added boost of power to your engine too! Filter Neck Outer Diameter:90mm Filter Neck Length:20mm Filter Base Width:195mm Filter Top Width: 120mm Filter Overall Length:140mm Filter Material: 15mm Dual Layer Foam Filter Base Material:Rubber polymer