Polymer Solutions has patented the all-plastic TierStack® Modular Bottled Rack System. It is the first US patent on an open top plastic transportation rack for bottled water. The TierStack® is similar in design to the ProStack™, but is lighter, more economical and has more flexibility. With a modular design and durable plastic casing, the TierStack® is designed for bottlers limited by rack weight and the high initial cost of rack float conversion.