In the Division you have possibility to change some attributes of your gear. Recalibration is the process of re-rolling of your gear pieces bonuses. You can do it if you have good gear but one of its properties doesn’t meet you.
At first you should upgrade the Recalibration in the Tech Wing. It will open up for you not only the Stat Switch perk but you can also use the Recalibration Station.
You can re-roll only one of your masks, armour, holsters, gloves, backpacks, knee pads pieces characteristic. On the right part the list of possible recalibrations will be opened. Before you start the re-rolling process take into account that in future you will be able to improve only changed attribute.
You will be able to re-roll one of your gear several times but you will be locked in this category of bonuses.
Watch the video to look the process in details.