If you carry a red dot and you are buying an optic-ready holster, the question that actually matters is not the brand of your sight. It is the footprint. The footprint is the mounting pattern on the bottom of the optic and the matching cut in your slide, and it is what determines whether a holster clears your dot cleanly. This guide breaks down the three footprint families you will run into most, how to tell which one you have, and what to confirm before you order.
What a footprint actually is
An optic footprint is the arrangement of mounting screws, recoil lugs, and the overall shape on the underside of a red dot. Slides are milled to match a specific footprint, and optics are built to sit in one. Two sights from different brands can share the same footprint, which is why footprint, not brand name, is the thing to know. For a holster, the shell has to be molded with enough room for the optic body and its mounting so nothing drags on the draw.
The RMR footprint
The RMR pattern is one of the most widely copied in the industry. A large number of red dots are built to drop directly onto an RMR-cut slide, which makes it a common default. If your slide was milled for an RMR or your optic advertises RMR compatibility, this is your footprint. Because it is so common, it is well supported across holster options.
The Holosun 507 series
The Holosun 507 series is enormously popular for concealed carry because it packs a lot of features into a compact enclosed or open-emitter body. The 507C and 507K are frequent choices on carry pistols. If you are running a 507-series optic, you want a shell cut to clear that specific body, which is taller and shaped differently than a bare slide.
The Romeo footprint
Sig's Romeo optics, including the Romeo family found on many optic-cut Sig pistols, use their own footprint. If you bought an optic-cut Sig and paired it with the factory or matching Sig optic, this is likely what you have. As with the others, the holster needs to be formed with clearance for that optic sitting on the slide.
How to tell which one you have
There are three reliable ways to identify your footprint. First, check what your slide was cut for, which the manufacturer lists by footprint name or by an adapter plate number. Second, check your optic's spec sheet, which states the footprint it uses. Third, if you run an adapter plate between the slide and optic, the plate is keyed to a specific footprint and is often the clearest answer. When in doubt, match the optic model to its published footprint rather than guessing from the shape.
What a TUKD shell clears
Here is the part that matters for buying. Every TUKD model except the Walther is cut for most slide mounted red dots including RMR, Holosun 507 series, and Romeo footprint. That covers the three families above, which are the ones the overwhelming majority of carry optics fall into. The Walther product does not make an optic-clearance claim, so if you carry a Walther PDP with a dot, contact us to confirm fit before ordering rather than assuming clearance.
If your optic uses a footprint outside those three families, confirm before you order rather than assuming it will clear. You can read more about optic clearance and what to verify on the optic-ready IWB holster guide.
What to confirm before you buy
Three checks cover it. Confirm your footprint is one of the covered families. Confirm you are selecting the exact pistol model at checkout, since optic-cut and standard versions of the same gun differ. And if you run very tall or suppressor-height sights along with the optic, factor that into your sight picture over the shell. Get those three right and the shell clears your setup as intended.
Picking the shell
Once you know your footprint and your exact model, choosing the shell is simple. For a Glock running a dot, the TUKD ORIGIN for Glock is where you configure the fit for your slide. Every shell is hand-formed Kydex with pre-tuned retention and no adjustment screws, and each one is retention-tested before it ships, so the draw is consistent from the first day.
The bottom line
Footprint beats brand name every time when you are matching an optic to a holster. Identify whether you are running RMR, Holosun 507, or Romeo, confirm your exact pistol model, and you are set, because those three families are covered across every TUKD model except the Walther. TUKD shells are made in Las Vegas and backed by a lifetime warranty, so a correctly matched optic-ready holster is a buy-once decision.