This is a factory FN 510 Tactical 10mm 22-round extended magazine.

Featuring a nickel-coated steel body and a true 22-round capacity, this is a must-have accessory for your FN 510 Tactical pistol.

FN’s new 510 Tactical is a 10mm striker-fired pistol inspired by their popular 509 series pistols. Its grip and frame are ergonomically designed and textured to assist in handling the strong recoil of the 10mm cartridge, while also featuring ambidextrous controls.