This is a genuine AAM 11.5 complete helical type posi differential. This is the style that came out in the 2003 and newer Dodge's, but also make a great replacement for the GM trucks with the govloc style posi. Please be aware that not all of these listed on ebay are genuine AAM. Shipping is a flat $25.00 in the continental U.S. which does not include Alaska or Hawaii.