This is for the people who hate getting their fingers pinched by the feed lips of their steel AICS mags. This loader is sized just right for loading .308 sized cartridges including 6 Dasher, 6BR, 6GT, 6 Creedmoor, 6.5 Creedmoor, etc, etc. My own twist on a product that's been out a while. I just made it a little more comfortable to use. 
 
Is it necessary? Nope. Is it convenient to use. Of course.