The extremely rigid STACC two-screw design allows ease of access while fusing multiple levels. The central cavity can be packed with bone graft or substitute for optimal fusion. There are 2 versions of STACC, namely the STACC tapered (or wedged) design which has a 8° (4° either side) taper in order to maintain lordosis when fusing multiple levels. The other, design, the STACC Domed features an anatomically correct dome for superior seating for single level fusions.