Check the listing for details. Bass Drum Bag 14"x20". Condition: New without tags. Listed at 140.89 USD. The innovative cases feature several major breakthroughs in their design, including the patented “TruForm” teardrop shape and “DynaZip” multi-directional zipper. The “DX-Core” internal padding system ensures top notch protection to your drums. These drummer-friendly designs not only advance the state-of-the-art, they completely change the conversation about the reliability, safety, and the convenience of soft drum cases. "TruForm" ShapeThe shape of each case corresponds to the “true” shape of the drum plus its mounting hardware. The universal, teardrop design allows a much snugger drum fit. It also allows dealers to reduce their inventory by eliminating the need to double-stock separate bags for tom-toms with and without suspension mounts and bass drums with and without tom mounts.DynaZip.