0.350 front sight, it's as low as you can get, taller sights will be easier to use but take up more space in the window. But RMR HD's window is huge so it's not a big deal.
Originally Posted By Duffy: 0.350 front sight, it's as low as you can get, taller sights will be easier to use but take up more space in the window. But RMR HD's window is huge so it's not a big deal.