ProMag Industries COL04 Magazine delivers exceptional reliability and performance for firearm enthusiasts. Built with precision and durability in mind, this magazine promises to enhance your shooting experience. Crafted from premium materials, it features a heat-treated chrome silicon spring, ensuring longevity and consistent performance. American-made quality is apparent in every facet of construction, making it a trusted choice for shooters. Heat-Treated Chrome Silicon Wire Spring Manufactured & Assembled in the U.S.A. Easy Loading Rugged Construction Choose reliability with ProMag COL04 Magazine, guaranteed for life against defects.