The Gage Assault Pack Add-on for PAYDAY 2 has 10 achievements.
Kill 25 Bulldozers using the Gewehr 3 Rifle. Unlocks the "Sniper Barrel" for the Clarion rifle, "Sniper Stock", "Sniper Grip" and "Sniper Foregrip" for the Gecko 7.62 rifle, "Precision Stock", "Precision Foregrip", "Precision Grip" and the "DMR Kit" for the Gewehr 3 rifle as well as the "Black Death" mask.