Gear Shift is a trait in Destiny 2 that can appear on 32 weapons. An enhanced version exists on crafted and some newer weapons.
What Gear Shift does
Reloading after a final blow or becoming amplified grants a period of increased damage. Stacks 5x.
Enhanced version
Reloading after a final blow or becoming amplified grants a longer period of increased damage. Stacks 5x.