This is an upgrade for the Lee Loadmaster progressive reloading press. This was designed to correct the problem with .223/5.56 shells tipping when using the case feeder. It is taller and has a ramp to help center the cases as they drop. There are also multiple holes for the vertical slider to allow for better adjustment. This is not a replacement for proper set up of the press. If you are having trouble try looking at the setup and adjustment documents for your press.