All the models below have a shorter core for blower clearence. This Direct Fit radiator features two rows of 1″ tubes, which doubles the cooling capacity of a factory single row. Our exclusive “press formed” end tanks are hand tig welded by expert craftsman, eliminating the factory plastic tanks. This heavy duty radiator features both an EOC (left side) and TOC (right side). This is a true Direct Fit for 2005 & 2006 Z51 option cars. 2007 Z51 did not have the EOC option. (Use 1139125A for 2007-09 with Z51) DEW-1139125B. FREE SHIPPING PLEASE ALLOW 7-10 DAYS FOR SHIPPING.