Convertible tops are a style of boat top that attaches to the windshield with use of snaps. This kind of top typically has two or three frames. Many times there are side curtains and an aft curtain that zip to the top. This dvd teaches you how to make patterns for the top and curtains in one trip to the boat. This  saves time and money by eliminating multiple trips to fit each piece. The process introduces you to the "Dot System" of patterning. It also explains how to "work" the patterns in preparation for cutting and sewing.