This ProMag RUGA33 Standard magazine holds 17 rounds of 9mm Luger ammunition and is designed to fit Ruger SR models. It is made from heat-treated steel, ensuring strength and reliability. The magazine includes an injection molded follower and a spring constructed from chrome silicone wire. Made in the USA.Key FeaturesCapacity: Holds 17 rounds of 9mm Luger ammunition.Material: Constructed of heat-treated steel for enhanced durability.Included Components: Features injection molded mag follower and chrome silicone wire spring.