4-1/4 IN to 4 IN Reducer: This coupling features a 90 Degree angle and is designed to connect to tubes with a 4 IN and 4-1/4 IN diameter. It's commonly used on aFe POWER cold air intake systems, but can be used for a variety of projects.Silicone Construction: Its silicone construction features four layers of polyester reinforcement, making it less prone to deformation, tearing, and other damage, than average couplings. Its extreme durability makes it perfect for forced induction applications. The built-in fitting (3/4 IN OD x 1 IN L) allows for easy connection to a PCV line.Stainless Steel Clamps: Two corrosion-resistant stainless-steel worm clamps (#064 & #072) are included, providing a secure seal for virtually any application.Direct Replacement for P/N 05-01464.