Getting the urethane bead right is the difference between a clean, quiet Bmw M4 sunroof glass replacement and one that develops edge lift, leaks, or highway whistling later. The bead is a designed gasket and structural interface, so we target an OEM-consistent route, height, and continuity-not "more is better." A uniform bead supports the glass at the intended level, creates a complete perimeter seal, and provides an elastomeric buffer that reduces NVH as the roof flexes and the vehicle sees temperature swings. Because urethane starts to skin after dispensing, sequencing matters. Before we pull the trigger, Bang AutoGlass confirms reference points, verifies how trims will sit, and ensures the glass will land squarely. Then we dispense within the product's working time so the adhesive can achieve full wet-out. We use a high-thrust gun and a properly notched nozzle to keep bead width and height consistent, especially at corners where stop-and-start application can leave thin spots. During placement, we lower the glass in one controlled set and apply even perimeter pressure to achieve consistent compression without smearing the bead or trapping air. When executed correctly, the bond line on a Bmw M4 stays sealed, flush, and stable-built to handle vibration, rain, and daily driving without common callbacks.