The 458 Lott is simply the 458 Winchester extended by half of an inch. This provides enough powder capacity to avoid the severe powder compression that is common with the 458 Winchester, when 500 gr bullets are used and the goal is the listed factory velocity. The longer case provides more flexibility on powder selection and easily provides 2300 fps with a 500 gr bullet. This brass is packaged in lots of 20. Shipping weight is 340 g/20 cases.