Hi John, this is a SA/DA pistol.
Stay safe & have a great day!

Hi John and welcome. This is a DA/SA firearm. Although I am sure you are familiar with DA/SA operation, just in case : the first shot, the trigger pull both engages the hammer and fires the firearm, but in subsequent shots, the slide traveling rearward during recoil does that. Cheers, stay safe and enjoy!

Used Sig Sauer P220 Match Elite 10mm W/Box And Four 8 Round Magazines. Features 5 Inch Barrel. Double/Single Action. SIGLITE Tritium Night Sights. Stainless Steel Frame Finish. Nitron Slide Finish. G-10 Piranha Grips. Weighs 39.1 OZ. Excellent Condition.