VKS (ВКС) or VSSK (ВССК) is a Russian bullpup, straight-pull bolt-action, magazine-fed sniper rifle chambered for the 12.7×55mm STs-130 subsonic round.

The weapon is also known by the name VSSK and the additional name Vykhlop (Выхлоп), "Exhaust", which comes from the development program.

The 12.7×55mm VKS silenced sniper rifle is intended for special operations that require silent firing[1] and penetration much superior to that provided by 9×39mm VSS silenced sniper rifle.

Typical targets for the VKS are combatants in heavy body armor or behind cover.

The accuracy is claimed as 1 minute of arc at a 100-meter range with precision bullets.