K03 K03S Upgrade Turbo For A3 A4 TT For Seat 1.8T K04-001 53049500001 Turbocharger Turbine This turbocharger is designed as an upgrade replacement for K03 and K03S applications, compatible with select 1.8T engines found in models such as A3, A4, TT, and Seat.Engineered to fit the K04-001 specification, it features the OEM 53049500001 for precise matching.The unit includes a turbine assembly built for performance improvement and under increased load.Installation requires standard tools and mechanical knowledge.all connections and seals are secure prior to engine startup.This is not an OEM product.Brand/model references are included solely to assist with compatibility identification.