PROMAG SIG MPX 9MM 50RD DRUM POLYMER Manufacturer Model Number: DRM-A21 Manufacturer: ProMag Model: SIG MPX Drum Caliber: 9mm Type: Accessory-Magazines Item Type: Accessory Firearm / Accessory Capacity: 50 rd. Shipping Weight: 1.8 Feature: Blued Steel Feature: Fits Sig MPX Optic Adjustable Objective: false Optic Reticle Illuminated: false