It bolts directly to the exit of the Catalytic Converter/ front pipe on all Astra Mk4 1.7 DTi DIESEL engined VAN & ESTATE models built in the period Jan 1998 through to April 2003. The HOFFMANN performance rear silencer is manufactured from aluminised mild-steel and features a polished stainless-steel Single 3 diameter tailpipe with an internally rolled tip. The silencer-less performance'Race Tube' centre pipe is manufactured from high-grade aluminised mild-steel. A performance improvement is achieved by improving the flow through the system. NOTE : THE IMAGE SHOWS THE ACTUAL HOFFMANN ASTRA MK4 VAN / ESTATE SYSTEM.