Most of the swimmers who broke 42 world records since February wore Speedo's LZR. Some of the swimmers claiming records were not the most practiced, implying the swimsuit must have helped. Four innovations came together to make the LZR. One, densely woven, extremely lightweight nylon-elastane fabric compresses the body into a hydrodynamic shape without sewn seams. Since seams 'act as speed bumps in the water,' LZR seams are ultrasonically welded, which removes 6 percent of drag, according to Speedo's Aqualab executive Jason Rance. Two, an 'internal core stabilizer' is a sort of 'corset that holds the swimmer's form,' maintains a tubular shape, reduces drag and requires less exertion, enabling a longer swim. Testing found that swimmers wearing the LZR consumed 5 percent less oxygen than swimmers wearing normal swimsuits. Three, strategically placed polyurethane panels have reduced drag by another 24 percent. And four, LZR's 3D shape fits 'like a second skin' and doesn't lie flat but remains shaped. The LZR costs $600 and takes 20 minutes to don. The Beijing Olympic swimmers believe they will lose the contest without an LZR. Olympic director of the American team Mark Schubert believes the LZR has improved performance by, maybe, 2 percent, a big improvement when counting tenths of a second, in which first place and fourth place are measured. Rival swimsuit maker Arena said the LZR situation is 'unprecedented' and tried to get the garment rules reviewed by the Olympics' governing body, FINA. Another rival swimsuit maker TYR Sport is suing Speedo's parent company Warnaco Swimwear and Schubert as well as others for breaking antitrust rules. It wasn't until April that FINA approved the use of polyurethane in racing swimsuits. Speedo's tech lead might not last long, however, because new swimsuits from Arena, Adidas and Mizuno were just approved by FINA.