The Apex J-Plate directly replaces the factory base pad on the Magpul GL9 PMAG for Glock. The J-Plate is 6061 hard coat anodized aluminum, and features laser marked identification dots. The base pad is easily installed, utilizing the factory retention plate. The base pad also adds additional weight for fast magazine changes. Features: Direct drop-in replacement of factory base pads Utilizes factory retention plate Adds approximately 0.045 oz to the magazine weight