If you remove your factory moderator and the threads look like exhibit B, select the .30 specific adapter A110.
To pick the correct adapter, you will need to measure the length of your carbon fiber shroud.
If your shroud measures 13 or 17 inches, you'll need A57.
If your shroud measures 11.5 inches and you eventually want to use a longer bottle(580 cc) you'll need A72
If your shroud is 11.5 inches long and you have no intentions of adding a longer bottle then go with A73
Easy to install 1/2 x 20 adapter for the LCS SK19. Convert your shroud to accept any 1/2 x 20 suppressor of your choice. I would highly recommend a Ronin one size up from what the gun's caliber is. Still very effective but more importantly reduces the chance of pellet clipping, especially during rapid fire.