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GLOCK 21 SF

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109 documented listings67 fit unconfirmedBrowse categories ↓

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What the compatibility labels mean
How we knowHow we check compatibility
  • Lab testedFit checked by Firearm Lab for the recorded setup.
  • Documented fitmentSupported by manufacturer, partner, or reviewed community evidence.
  • Interface matchMounting details match, but this exact model and part have not been confirmed to fit together.

Check your exact model and part before ordering. Fitment limits

Model details
Manufacturer
GLOCK
Model & version
Glock 21 · SF
Mounting details
Glock Accessory Rail, Glock rear-sight dovetail (standard and Slimline slides)
Compatibility records
176

Sights

Sights

90 listed
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Lights & rail fitment

Lights & Lasers

54 listed
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Triggers & internals

Triggers

12 listed
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Recoil Springs

1 listed
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Optics & footprint adapters

Optic Plates

7 listed
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Also on this pistol

Holsters

6 makers

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Holster makers (6)

Grip & magwells

Base Pads

2 listed
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Barrels & comps

Compensators

1 listed
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Categories with no listings (10)

About the GLOCK 21 SF

Manufacturer listing ↗ · Checked 2026-08-02

Type
Pistol
Manufacturer
GLOCK
Model & version
Glock 21 · SF
Caliber
45 ACP
Mounting details
Glock Accessory Rail, Glock rear-sight dovetail (standard and Slimline slides)
Width
1.34"
Height
5.51"
Weight
26.1 oz
Slide width
1.12"
Slide length
7.6"
Barrel length
4.61"
Overall length
8.07"

Other versions of the Glock 21

Compare versions and check the details for your exact model.

  • GLOCK 21Same recorded mounting details. Check each part for additional requirements.
  • GLOCK 21 Gen 2Lacks: Glock Accessory Rail.
  • GLOCK 21 Gen 3Same recorded mounting details. Check each part for additional requirements.
  • GLOCK 21 Gen 4Same recorded mounting details. Check each part for additional requirements.
  • GLOCK 21 Gen 5Same recorded mounting details. Check each part for additional requirements.
  • GLOCK 21 MOSAdds: Glock MOS. Lacks: Glock rear-sight dovetail (standard and Slimline slides).
  • GLOCK 21 V MOSAdds: Glock MOS. Lacks: Glock rear-sight dovetail (standard and Slimline slides).