Shield Arms S15 Glock 43X/48 9mm 25 Round Pistol Magazine w/ Pre-Installed Magazine Extension Black. Using another manufacturer s catch or failing to upgrade may result in reliability issues. S15 magazines are designed to work exclusively with Shield Arms steel mag catches. Specifications for Shield Arms S15 Glock 43X/48 9mm 25 Round Pistol Magazine w/ Pre-Installed Magazine Extension: Manufacturer: Shield Arms Color: Black Fabric/Material: Aluminum Magazine Capacity: 25 Round Caliber: 9mm Luger Gun Make: Glock Gun Model: Glock 48 Glock 43X Features of Shield Arms S15 Glock 43X/48 9mm 25 Round Pistol Magazine w/ Pre-Installed Magazine Extension Magazine: 25+1 total round capacity Same base length as OEM Glock 43X/48 magazines Pre-installed anodized Shield Arms S15 +10 Extension (black anodized) Works with Shield Arms Carry or Premium Magwell Black Nitrocarburized QPQ finish Mag Extension: Type-2 black anodized finish Adds 10 rounds to the S15 magazine Unique easy-access floor plate design for servicing or cleaning without removal Index cuts on the extension body to improve grip when drawing from a magazine pouch Light but sturdy - machined from billet 6061 aluminum Comes with a 15-coil plus power spring Compatible with Shield Arms S15 magazines only Works with Shield Arms Carry or Premium Magwell Fits most aftermarket flared mag wells Package Contents: Shield Arms S15 Glock 43X/48 9mm 25 Round Pistol Magazine w/ Pre-Installed Magazine Extension (1) S15 Gen 3 Magazine (1) Pre-installed black anodized Shield Arms S15 +10 Magazine Extension What firearm models does the manufacturer say Shield Arms S15 Glock 43X/48 9mm 25 Round Pistol Magazine w/ Pre-Installed Magazine Extension is compatible with? The manufacturer says that Shield Arms S15 Glock 43X/48 9mm 25 Round Pistol Magazine w/ Pre-Installed Magazine Extension is compatible with Glock 43X Glock 48Shield Arms S15ME10INSBLK: S15 Glock 43X/48 9mm 25 Round Pistol Magazine w/ Pre-Installed Magazine Extension Black