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FN 66100464 509M 9mm Luger 4" 10+1 Black Interchangeable Backstrap Grip

  • Pistol
  • 9mm
  • Double action
  • 10 rd capacity
  • 4" barrel
UPC 00845737010027

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1 offer · 1 in stock · sorted by best price
RetailerPriceStockLast checkedDeal
East Valley Tactical$665.67In stock (10)34m agoGo to deal

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Description

Upgrade your EDC with the FN 509 Midsize. This ideal combination of a four-inch slide and barrel with a midsize frame retains full-sized pistol performance in an easily-concealed package. The improved controls aid in manipulation, while the improved texturing on the two included backstraps provides better recoil management and a, flatter faced trigger allows for more controllable trigger press and cleaner break. Its polymer constructed frame features fully ambidextrous controls, MIL-STD-1913 accessory mounting rail and cold hammer-forged stainless steel barrel with a recessed target crown. The slide is easily racked, and features combat-style sights and improved front and rear cocking serrations. The 509 Mid-Size ships with two interchangeable backstraps and FN logo soft pistol case. This model has a black finish, 3-dot luminescent sights, and comes with two 10-round magazines.

Specs

BrandFn
CategoryPistol · Firearms
Caliber9mm
UPC00845737010027
Capacity10Rd
Weight26.5 oz
Oal7.40"
HandRight
SizeMid-Size
TypeStriker Fired
ColorBlack
GripsBlack Interchangeable Backstrap
Model509M
StockPolymer Frame / Black Polymer Grips
ActionDouble Action Only
FinishColored
SafetyNo Manual
SeriesMid-Size
SightsFixed 3-Dot Luminescent
Includes2 Magazines/Soft Pistol Case
Magazine2 / 10 rd.
Accessories2 Mags
Barrel_typeRecessed Target Crown
FinishcolorBlack
Frame_colorBlack
Sight_styleContrast
Slide_colorBlack
Frame_finishBlack
Max_capacity10
Slide_finishMatte Black
Barrel_length4"
Grip_materialPolymer
Similar_itemsHG9MM
Frame_materialPolymer
Slide_materialStainless Steel
Type_of_sightsFixed
Weight_in_ounces26.5
Frame_descriptionBlack Polymer
Magazine_capacity10
Slide_descriptionBlack Steel
Barrel_descriptionCold Hammer Forged
Barrel_length_range4" to 4.99"
Sight_configuration3 Dot
Type_action_functionSemi-Auto
Barrel_length_in_inches4
Number_of_magazines_included2
Package dimensions2.55 x 8.25 x 11.3 in

D.O.P.E.Price history

Lowest price across connected retailers, from every price check we've recorded.

Current best
$665.67
Low
$665.67
Oct 8, 2026
High
$665.67
Oct 8, 2026
Tracking since
Oct 8, 2026
One price check so far ($665.67 on Oct 8, 2026). The chart fills in as retailers are re-checked.
Recent price checks (1)
DateRetailerPriceStock
Oct 8, 2026, 5:15 PM PTEast Valley Tactical$665.67In stock

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