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GLOCK 21

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110 documented listings71 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
Mounting details
Glock Accessory Rail, Glock rear-sight dovetail (standard and Slimline slides)
Compatibility records
181

Sights

Sights

91 listed
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Lights & rail fitment

Lights & Lasers

57 listed
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Also on this pistol

Holsters

9 makers

Check each manufacturer’s options for your model, light and optic.

Holster makers (9)

Optics & footprint adapters

Optics

1 listed
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Optic Plates

7 listed
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Triggers & internals

Triggers

8 listed
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Barrels & comps

Barrels

5 listed
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Grip & magwells

Base Pads

2 listed
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Slides

Slides

1 listed
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Categories with no listings (9)

About the GLOCK 21

Type
Pistol
Manufacturer
GLOCK
Model & version
Glock 21
Caliber
45 ACP
Mounting details
Glock Accessory Rail, Glock rear-sight dovetail (standard and Slimline slides)
Width
1.34"
Height
5.51"
Weight
26.28 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 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 SFSame recorded mounting details. Check each part for additional requirements.
  • GLOCK 21 V MOSAdds: Glock MOS. Lacks: Glock rear-sight dovetail (standard and Slimline slides).