340 with metal in oil pan

They are retainer keeper Halve bottoms. Any idiot can see that. I had a fresh set of heads done at a local shop with most all the retainers broke and all over the motor. 68 4spd. motor with the 555 lift cam factory. They were the green sets of locks and they were new. No pistons were hitting, motor ran good,we were changing the pan when we found them. The retainers were wore and new keepers were installed with shot retainers when they installed seals. It is a common find on heads redone with cheap locks. The old green ones that shops bought in quantity.