Wilson-Rogers series 47 advanced Pistol Magazines for 1911 style Autos are the choice of experienced competitors and the U.S. Military Elite Special Forces. Stainless steel magazines are designed with maximum durability and reliability in mind. The self-lubricating followers are made from blended Fiber-Fill nylon as is the removable base pad. The standard base pads are .350_ thick. Springs are specially fabricated from a heavy duty, high tensile strength spring wire to reduce _spring set_ and provide the longest possible spring life. Increases Reliability in ALL 1911 Pistols Aircraft Grade Certified Stainless Steel Tube Resists Corrosion .027" Tube Walls - Thickest In The Industry Tubes are Heat Treated for Maximum Durability and Service Life Fiber-Fill Nylon Self-Lubricating Follower Provides Smooth Round Feeding Maximum Tensile Strength Heavy-Duty Spring for Long Service Life, Enhanced Feeding and Positive Slide Stop Operation Removable .350" Plastic Base Pad for Easy Maintenance and Versatility with Different Base Pad Options No Other Magazine on the Market Can Compare for Proven Inherent Reliability, Durability and the Ability to Remain Loaded for Long Periods of Time Without Damage