The Voss Compensator muzzle attachment in The Sinking City 2 is a very useful firearm accessory. To obtain the Voss Compensator, you can open the first Emergency Response Crate, but you'll need to acquire an Emergency Response Crate Activation Pen first. This crate is located on the first floor of the library.
How to Obtain the Voss Compensator Muzzle Attachment in The Sinking City 2