Thanks 4sp. As I said, I am not much of a mechanic, but the rep at Falcon and Rich at Packard told me that the kit was a HiPo rebuild kit. Currently, the pistons are at the machine shop as they needed them for boring the block for the 30 over plus clearance. I did take one of them out of the packaging, and they do have the two valve relief and the dome on the opposing side. Could it be that the Falcon, Packard, Katner, Egge pistons are built as a form of the original commando piston....therefore they do not look like commando pistons? I can post a photo of one of the pistons this coming week when I get the block back. The original pistons that were taken out of the original 273 block that is being decked and bored were the 4 valve relief. Thanks, I appreciate your input. Old Dart 66