Glock 19/45 with Surefire X300 IWB Holster

Inside Waistband Holster for Glock 19 and 45 with Surefire X300U-A or X300U-B

This inside waistband (IWB) taco-style holster is engineered specifically for the Glock 19 and Glock 45 equipped with the Surefire X300U-A or X300U-B weapon-mounted light. Retention is secured on the light body—not the pistol—so the holster requires the light to be mounted during use.

Firearm & Generation Compatibility

Select the correct Glock generation for optimal fit: Glock 19 Gen 5 or Gen V, Glock 45 Gen 5, or Glock 19 Gen 3/4. This holster is also compatible with the Glock 23 Gen 3 & 4, but not compatible with the Glock 23 Gen 5.

Precision Fit & Craftsmanship

Each holster is vacuum-formed using a precision-machined mold shaped from a CAD model of the exact firearm and light combination. Every holster is formed, trimmed, folded, and finished in-house. Final fit and function checks are completed with the actual pistol and X300U light installed to verify reliable retention.

Retention can be easily adjusted to suit your preferred draw resistance.

Surefire X300U-B Light Information

Learn more about the Surefire X300U-B light at the official Surefire X300U-B information page .

The recommended light for this holster—the Surefire X300U-B—can be purchased directly from us at Surefire X300U-B Weapon Light (Four Brothers Holsters) .

Barrel, Threaded Barrel & Compensator Clearance

The holster accommodates threaded barrels and compensators that match or stay within the slide’s height and width. Compensators extending past the slide will protrude slightly from the open muzzle end of the holster.

Features

• Constructed from durable .093" thermoplastic
• Adjustable retention for personalized draw feel
• High sweat guard standard (medium and low options available by request)
• Holster profile cut to allow clearance for most red dot sights
• Minimal material with smooth, comfortable edges
• Optional ModWing with two inserts to tune belt leverage and reduce printing under clothing
• Proudly made in the USA

Belt Attachment Guidance

For help choosing between belt and no-belt attachment options, see our detailed guide: Inside Waistband Belt & No-Belt Attachment Options Explained .

Magazine Carrier Options

Compatible magazine pouches are available in both IWB and OWB configurations:

• Glock 9/40 IWB Magazine Pouch
• Glock 9/40 OWB Magazine Pouch

Color Options

For guidance on Kydex color and pattern choices, visit our Holster Color Guide .

Maintenance Recommendation

We strongly recommend applying a removable thread locker to all holster screws once adjusted to prevent screw loss during use.

FAQs

Does this holster require the Surefire X300U-A or X300U-B to function?

Yes. Retention is based on the light body, so the firearm must have the X300U-A or X300U-B attached.

Will this holster fit the Glock 23?

It fits the Glock 23 Gen 3 and Gen 4. It does not fit the Glock 23 Gen 5.

Is the holster compatible with red dot sights?

Yes. The holster profile is cut to clear most red dot sights, including optics that overhang the slide.

Will threaded barrels or compensators fit?

Yes—provided they match the height and width of the slide. Longer compensators will extend slightly beyond the muzzle.

Can I adjust the retention?

Yes. Retention screws allow you to fine-tune the draw tension.

Does the Glock 19 Gen V fit this pistol?

What belt attachments work best?

Attachment selection varies by carry style. See our IWB Belt Attachment Guide for detailed recommendations.