Set of 8 Big Block High Compression Chevy pistons GM 3959105 and green code dimple rods. The rods are 6.135 in length with 7/16 hardened bolts. GM and TRW cast into the bottom inside. They ar L-88/ZL-1 12.4-1 open chamber pistons? So far have only looked at 1 out of the 8.