The CTA Manufacturing 4-pc GM Cam Holder Set, No. 7728, services the left and right head for 2006+ 2.8L, 3.0L, and 3.6L V6; and 2004+ 3.5L I5 and 4.2L I6 GM engines. The tool is designed to prevent rotation during timing chain service. The set includes: 7677X01 (EN-48383-3), 7677X02 (EN-48383-1), 7677X03 (EN-48383-2), and 5047 (J-44221).