Straight Line Launch Pad 540 Single Ballast Bag 2010: Get straight down to business with the Straight Line Launch Pad 540 Single Ballast Bag. This is the easiest and cleanest portable ballast system on the market, and when striving for efficiency, clean and easy is always the best way to go. Made of heavy duty 30 Gauge PVC with strong, electronically welded seams, this bag is tougher than that high school bully you miraculously managed to give a black eye in the ninth grade.