Holster Mount Fitment & Compatibility Guide

Not sure if a Flat Head Supply Co. holster mount will fit your firearm or Tesla? This guide explains how fitment works, what measurements matter, which accessories may affect compatibility, and what to check before ordering.

Flat Head Supply Co. holster mounts are designed to make vehicle storage more organized, secure, and purpose-built. Firearm fitment is based primarily on the slide, while Tesla fitment depends on the specific vehicle interior, model year, and console or door pocket geometry.

This guide is intended to help you choose the correct mount with confidence while avoiding assumptions about universal fitment.

Firearm Fitment Overview

Flat Head Supply Co. holster inserts are designed to retain the firearm by the slide.

The insert does not rely on the grip, magazine, trigger guard, or frame for fitment. Because of that, compatibility is primarily determined by the width and shape of the firearm’s slide, along with any accessories mounted near the slide, barrel, rail, or muzzle area.

The current insert design should be considered compatible with firearm slides measuring up to 30mm wide.

This 30mm guideline provides a practical fitment buffer and helps account for small differences between firearm models, slide coatings, manufacturer tolerances, and accessory setups.

In general, the mount is most likely to fit compact, subcompact, and slim-profile handguns with slide widths at or below 30mm.

What Determines Firearm Compatibility?

The most important firearm fitment factors are:

  • Slide width
  • Slide shape and profile
  • Optics or optic plates
  • Threaded barrels
  • Compensators
  • Rail-mounted lights
  • Rail-mounted lasers
  • Other accessories that protrude below, beside, or forward of the slide

The grip, magazine, and frame shape generally do not determine fitment because the insert does not retain the firearm from those areas.

Slide Width Requirement

The current Flat Head Supply Co. holster insert is designed around slides measuring 30mm wide or less.

This does not mean every firearm under 30mm is guaranteed to fit in every possible configuration. Accessories, aftermarket modifications, and unusual slide shapes can still affect compatibility.

However, slide width is the first and most important measurement to check.

How to Measure Slide Width

To measure your firearm’s slide width:

  1. Make sure the firearm is unloaded and safe to handle.
  2. Use calipers if available.
  3. Measure the widest part of the slide from left to right.
  4. Do not include the grip, magazine, frame, or controls in this measurement.
  5. If the slide measures 30mm or less, it is likely within the intended fitment range.

If you do not have calipers, check the manufacturer’s published slide width or overall width. Be aware that “overall width” may include controls, grips, or other features that are not part of the slide itself.

When in doubt, send us a photo and your firearm model before ordering.

Optics and Red Dot Compatibility

Most slide-mounted optics should not interfere with the insert because the mount is designed around the body of the slide rather than the optic itself.

Common red dot optics are generally expected to fit as long as they do not contact the insert or surrounding mount area.

Fitment may be affected by:

  • Oversized optics
  • Large optic plates
  • Optics that overhang the slide
  • Unusually low-mounted optic setups
  • Aftermarket slide cuts or adapter plates that change the slide profile

If your firearm has a red dot installed and you are unsure, send a side-view photo before ordering.

Threaded Barrels and Compensators

Threaded barrels and compensators may fit, but compatibility depends on the specific firearm and accessory setup.

A threaded barrel or compensator is more likely to fit if it does not protrude in a way that contacts the insert, front of the mount, or surrounding vehicle-specific mounting area.

Fitment may be affected if the accessory adds:

  • Extra width near the slide
  • Extra height near the muzzle
  • Forward protrusion beyond the slide
  • Downward protrusion that contacts the mount

If your firearm has a threaded barrel or compensator, check whether the accessory could interfere with the insert or mount body before ordering.

Lights and Lasers

Firearms equipped with weapon-mounted lights or lasers may require the light-clearance version of the mount.

The standard insert is designed around the slide area and is not intended to provide additional clearance for rail-mounted accessories below the barrel.

Choose the light-clearance version when available if your firearm has:

  • A weapon-mounted light
  • A weapon-mounted laser
  • A combination light/laser unit
  • Any rail-mounted accessory below the slide or barrel

If you are unsure whether the standard version or light-clearance version is correct, contact us before ordering.

Door Mount vs. Center Console Mount Firearm Fitment

The same insert shape and dimensions are used across Flat Head Supply Co. holster mount types, including both:

  • Tesla door pocket holster mounts
  • Tesla center console holster mounts

This means firearm-side compatibility is generally consistent between mount styles. If a firearm fits the insert in one mount type, the firearm-side fitment should be similar in the other mount type.

However, vehicle fitment is separate. The mount itself still needs to match your specific Tesla model, model year, and interior layout.

Tesla Vehicle Fitment

Tesla fitment depends on the physical shape of the vehicle’s interior storage area.

Different Tesla models and model years may have different door pocket shapes, center console layouts, storage bin geometry, and interior refresh designs. A mount designed for one Tesla interior may not fit another.

Before ordering, confirm that the product listing matches your:

  • Tesla model
  • Model year
  • Interior refresh style
  • Door pocket or center console layout
  • Storage bin shape
  • Existing organizer trays or accessories

A firearm may fit the insert, but the mount must also fit the vehicle location it was designed for.

Tesla Fitment Factors to Check

For door pocket mounts, check:

  • Vehicle model
  • Model year
  • Driver-side or passenger-side pocket shape
  • Door pocket depth and contour
  • Whether the pocket has changed between refreshes

For center console mounts, check:

  • Vehicle model
  • Model year
  • Console style
  • Console bin geometry
  • Upper tray or organizer interference
  • 12V outlet location, if applicable
  • Any aftermarket organizers already installed

If you are unsure which Tesla interior you have, send a photo of the intended mounting area before ordering.

Common Firearm Examples

The current insert is designed around slides up to 30mm wide. Many popular concealed-carry handguns may fall within this range depending on the exact model and configuration.

Examples include:

  • Glock 19
  • Glock 26
  • Glock 43
  • Glock 43X
  • Glock 48
  • Sig Sauer P365
  • Smith & Wesson Shield
  • Springfield Hellcat
  • Ruger Max-9
  • Taurus GX4
  • Canik Mete MC9

Note: This includes all versions of the above models

These examples are provided as general reference points only. Exact fitment can vary depending on aftermarket slides, optics, optic plates, lights, lasers, threaded barrels, compensators, and other modifications.

The best way to confirm compatibility is to measure your slide width and check for accessory interference.

What May Not Fit

Some firearms or configurations may not fit the current insert or may require a different version.

Fitment may be affected by:

  • Slides wider than 30mm
  • Oversized or unusually shaped slides
  • Full-size or competition-style slide profiles
  • Wide aftermarket slides
  • Large compensators
  • Threaded barrels that protrude into the mount area
  • Rail-mounted lights or lasers used with the standard version
  • Accessories that extend below, beside, or forward of the slide
  • Aftermarket modifications that significantly change the slide shape or width

This product should not be considered a universal firearm holster. It is a vehicle-specific mount with a slide-retention insert designed around a defined fitment range.

What to Do If You Are Unsure

If you are not sure whether your firearm or Tesla interior will fit, please contact Flat Head Supply Co. before ordering.

The most helpful information to send is:

  • Your Tesla model and model year

  • A photo of the door pocket or center console area

  • Your firearm make and model

  • Whether you have an optic, light, laser, threaded barrel, or compensator

  • Slide width measurement, if available

  • A side-view photo of your firearm setup

With clear photos and basic details, we can help determine whether the standard version, light-clearance version, or a different mount style is the better option.

Compatibility Summary

Flat Head Supply Co. holster mounts are designed around two separate fitment questions:

First, the firearm needs to fit the insert.
Second, the mount needs to fit the Tesla interior location.

For firearm fitment, confirm that your slide is 30mm wide or less and check whether any accessories may interfere with the insert.

For Tesla fitment, confirm that the mount matches your specific model, model year, and interior or console geometry.

For best results:

  • Measure your slide width before ordering.

  • Choose the light-clearance version if using a light or laser.

  • Check that barrels, compensators, or accessories do not interfere.

  • Match the mount to your Tesla model and interior style.

  • Contact us before ordering if you are unsure.

Frequently Asked Questions

Will this fit my specific handgun?

Fitment depends primarily on slide width and slide shape. The current insert is designed for slides measuring up to 30mm wide. If your slide is 30mm or less and does not have accessories that interfere with the insert, it is likely within the intended fitment range. For firearms with a slide width greater than 30mm, it is possible to adapt your order to accept this size slide width - please contact us for further information prior to submitting your order.

Does the mount hold the firearm by the grip or magazine?

No. The insert holds the firearm by the slide. It does not rely on the grip, magazine, trigger guard, or frame for retention.

Will it fit with a red dot optic?

Most slide-mounted optics should not interfere because the insert is designed around the slide body. Large optics, oversized plates, or accessories that overhang the slide may affect fitment. If you're unsure, please feel free to contact us for confirmation.

Will it fit with a threaded barrel?

A threaded barrel may fit as long as it does not protrude in a way that contacts the insert or surrounding mount area. Fitment depends on the firearm and barrel configuration.

Will it fit with a compensator?

Some compensators may fit, but larger or wider compensators may interfere with the mount. If the compensator expands the width or height of the slide beyond the stock dimensions, please confirm that the maximum is within the dimensions (30mm) capable of the original insert. If you have any questions or have a use case requiring a larger size, please contact us.

Will it fit with a weapon-mounted light or laser?

Firearms with lights or lasers may require the light-clearance version. The standard insert is not intended to provide additional space for rail-mounted lights or lasers.

Is firearm fitment different between the door mount and center console mount?

The same insert shape and dimensions are used for both door mount and center console mount types. Firearm-side compatibility is generally the same, but vehicle fitment still depends on the specific Tesla model and interior geometry.

Why does Tesla model year matter?

Tesla has changed interior layouts, door pockets, and center console geometry across different models and refreshes. A mount designed for one interior style may not fit another.

What should I send if I am unsure?

Send your Tesla model and year, your firearm make and model, any attached accessories, and a slide width measurement if available.

Is this a universal holster?

No. This is not marketed as a universal holster. It is a vehicle-specific mount with a slide-retention insert designed around a defined firearm fitment range.

Responsible Use Notice

Flat Head Supply Co. products are intended for lawful use only. Customers are responsible for understanding and following all applicable local, state, and federal laws related to firearm ownership, carry, transportation, and storage.

Always handle firearms safely and ensure your firearm is unloaded before checking fitment, measuring slide width, or test-fitting any accessory.