Specialization

Specialization is an upgrade path that upgrades the player's skill in the game, in the slowest speed possible. Yes it's true. So to get all these specialization items, one must play for a very long time, possibly 20 years (without sleeping or doing daily activities like bath or eat) to upgrade all.

Here's the list of specialization items in Battlefield Hardline:

Classes Upgrades
Operator Mechanic Enforcer Professional
 * Upgrade Chest Plate
 * Flak Jacket
 * Fast Repair
 * Repair Unit
 * Reduce Suppression
 * Increase Suppression
 * Advanced Spot
 * Fast Unspot

Vehicle Weapons Upgrades

 * 7.62mm Minigun
 * Coaxial HMG
 * Coaxial LMG
 * 25mm HE Shell
 * HVCC Flechette
 * Heatseekers

Vehicle Countermeasures Upgrades

 * Fire Extinguisher
 * IR Flares
 * Smokescreen

Vehicle Optics Upgrades

 * Zoom Optics

Vehicle Upgrades (the main upgrades)

 * Maintenance
 * Proximity Scan
 * Aircooler
 * Spotlight

Vehicle Gunner Upgrades

 * Gunner Zoom Optics
 * Gunner Proximity Scan
 * Gunner Spotlight
 * Gunner Aircooler