ASTRO PNEUMATIC 1-5/8 to 4-1/4 Exhaust Pipe Stretcher Kit - Metallic The ASTRO PNEUMATIC 78835 Exhaust Pipe Stretcher Kit provides a robust solution for expanding exhaust pipes, creating tight seals, and ensuring optimal exhaust system performance. This impact-driven expander kit includes a 28mm drive tool and a variety of collet sets designed to expand pipes ranging from 1-5/8 to 4-1/4. With its durable construction and user-friendly design, the ASTRO PNEUMATIC 78835 is ideal for professional automotive applications, simplifying exhaust pipe expansion and fitting tasks.