Britain received plenty of lend-lease Thompson M1928A1s. 

This kit contains an exclusive  special varient of it, the "Inline". The Thompson "Inline" as it's name suggests, has an inline stock which heavily reduces recoil. It also has assault rifle style sights, and utilizes similar tactics.

British Special Infantry comes with the following items:
-Thompson "Inline"
-Exclusive Mag Pouch Uniform

Once purchased, kit items are available in both singleplayer and multiplayer, provided CtB is installed. Purchased kits should become available immediately if connected to the official server, otherwise, try restarting the game.