Add some firepower to your SKS with this detachable replacement magazine from Promag Industries. This is a 40 round polymer gun mag that fits most model sks guns. This is a 40-rd magazine designed for SKS rifles and carbines. The magazine body and follower are constructed of a proprietary DuPontŪ Zytel based polymer to ensure a long service life. This magazine uses ProMag load um up and stack um up for years anti-fatigue springs.