Description Norbert’s 12cm Quad Bar Mat System for 6′ rails consists of four mats covered with 18 oz and coated vinyl material with Hook and Loop fasteners for easy attachment. For optimal footing, 12cm mats are filled with 3.5″ thick 75 ILD polyfoam with a top layer of 1.375″ crosslink.­ (13’6″ x 13’6″ space required.) Quad bar mats are also commonly referred to as Star Bar Mats. This system comes in two sizes: 6′ – This mat system consists of four (4), 72″ x 84″ x 12cm mats, that when connected create a 156″ x 156″ matted area, with a 12″ x 12″ inside opening for upright hardware. Four separate 9″ x 72″ Connector Flaps with Hook Connector are also included. 8′ – The larger mat system consists of four (4), 94″ x 106″ mats, that when connected create a 200″ x 200″ matted area, with a 12″ x 12″ inside opening for upright hardware. Find the 8′ mat system here. To fit SA-4000 upright hardware Pick different Quad Bar Mat System colors, or choose from our mats for 8′ rails option. Model: QD-516 IMPORTANT – CONSUMER WARNING & PRODUCT INFO – Click Here and please read carefully California Residents: Click Here for Important California Proposition 65 Warning Information If the shipping cost is not listed, Shipping costs will be emailed to you after your purchase. If you’d like a quote before buying, please call us at 877-496-7763.