Shuangyuan SY168 Polyurethane Seam Sealant – 300 ml Description Shuangyuan SY168 is a polyurethane sealant designed for automotive sheet metal weld seams. Supplied in a 300 ml cartridge, it combines easy application with a paintable and sandable finish for vehicle body repair and refinishing. Product Feature 1. Automotive Seam Sealing – Designed for sheet metal weld seams. 2.Paintable Finish – Can be painted after curing. 3. Sandable Surface – Supports surface preparation