This is a very nice set of used pistons for a 6 inch rod 400  .030 over 3.75 Stroke..As you can see from the pictures hardly any signs of wear...Rings are new 6 rings pairs are file fit and 2 pairs are drop in....Be sure to set your top end gap per kieth black instructions....So all rings will need gapped depending on you finished bore size and your preference...I will provide you a copy of kieth blacks instruction sheet...