This new variant I'm calling PelletgageR is intended to provide a rapid and accurate way to sort out the head size you want. Typically you would want two gages, one to exclude oversized pellets, and another to exclude undersized. All 48 the apertures on the gage plate are the same size. It is now offered for both .177 and .22 calibers, with options for the most popular specific head sizes. You will very likely find that sorting for one head diameter will yield tighter groups, and this is much faster than using the regular Pelletgage for that purpose.