An adjustable screed support system was needed on Phase 1: 100,000 sf with the slab depth varying 8 “to 12” on the LAX Integrated Express Solutions (LINXS) . The MAKO JAWS RailFin screed chair supports a 1/4” flat rolled steel rail. A T - Rail was designed – 1.5” x 0.25” with a 1.5” x 0.25” T-top – to act as a backbone to provide additional support for the mechanical screed.