This 24 round 9mm magazine is compatible with FN’s 509 Tactical, 509, FNS 9mm, and FNS-C 9mm handguns. The magazine is made of metal, features a black finish, and has 4-24 load indicators on the rear of the magazine. Due to its high capacity this magazine is ideal for plinking at the range, tactical operations, or home defense, holding only six rounds less than standard modern sporting rifle magazines.