Battlefield 1‘s In the Name of the Tsar expansion will bring with it new specializations that DICE hopes will give players “more opportunities and diversity” within each kit. In a recent post on Reddit, the developer explained the new specializations while noting that this is just the beginning and that it plans to add more in future updates.
Here are all the details:
How it works
Specializations are broken down into two different variants: Generic and Kit Specific. Every class has access to 7 Generic Specializations and 2 Kit Specific Specializations.
All players will start with 3 Specializations by default: Flak, Cover and Quick Regen. Further Specializations will be unlocked via completion of new Service Assignments (coming to all players with the “In the Name of the Tsar” expansion), but in the interest of testing and getting feedback, we have unlocked everything for you on the CTE. We will have more information about the Service Assignments at a later time. Specializations are designed to give players more opportunities and diversity within each kit, not necessarily more power overall. Choices should provide more depth and strategy to gameplay.
List of all Specializations
Generic:

Flak: Incoming damager from explosions is reduced by 15%
Cover: Incoming suppression is reduced by 25%
Quick Regen: Decrease time before Out of Combat Heal by 20%
Quick Unspot: Decrease length of time you are Spotted by 2 seconds
Bayonet Training: Bayonet cha...