Recommended for calibers greater than .338 and the light magnums. Snap closure and back security adjustment. Constructed from a material that absorbs recoil and spreads the actual recoil impulse over a longer length of time. This reduces the amount of felt recoil. The Past Super Mag Plus Shield has the same quality construction as all Past shields, but is designed to tame the real shoulder thumpers like the .416 Rigby and the .500 Nitro.