Holosun 509 Mounting Plate for Glock MOS 9mm
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The Holosun 509PLT-MOS9MM is a genuine Holosun adapter plate that mates a 509-series optic to the Glock Modular Optic System cut on 9mm slides.
Holosun's 509 body uses its own rear-lug pattern rather than the RMR or RMSc footprint, so it cannot be dropped straight into a factory optic cut — this plate is the piece that makes the two talk to each other.
It is machined from aluminium with a hard anodised finish, sized to the MOS pocket on the slide and drilled for the 509 lug pattern above it. Holosun list the plate as taking their 509-series sights and the AEMS-MACRO.
If you are building on a Glock MOS host — an airsoft gas blowback slide, a training gun or a long-barrelled competition pistol overseas — this is the part that lets a sealed 509 sit low and square on the slide instead of on a stack of shims. Worth saying plainly: Holosun do not publish what fixings are supplied with the plate, so if your slide screws have gone missing, tell us what you have before ordering. The plate is also 9mm-specific and will not suit .40 and .45 MOS pockets.
It fits Glock MOS 9mm optics-ready slides and carries a 509-series optic such as the enclosed 509T. Other hosts have their own plates in the same family — CZ P-10, FN 509 Tactical and RMR-cut slides.
| Type | Optic adapter plate |
|---|---|
| Optic Compatibility | Holosun 509 series and AEMS-MACRO |
| Host | Glock MOS optics-ready slides, 9mm |
| Material | Aluminium |
| Finish | Hard anodised |
| Brand | Holosun |
| MPN | 509PLT-MOS9MM |
Get the plate right and the optic sits where the factory cut intended it to. Order the 509PLT-MOS9MM today — imported from the USA with all duties paid by us and dispatched tracked from the UK in 7–10 business days, with nothing to pay on delivery.
Explore more: Optic Mounts, 509PLT for RMR-Cut Slides or browse all Holosun.
| Brand | Holosun |
|---|---|
| Part no. | 509PLT-MOS9MM |
| Category | Optic Mount |
| Barcode | 810047071020 |
£5 tracked UK delivery on every order via Royal Mail Tracked 24. Our products are ordered in from the manufacturer rather than held in UK stock, so please allow 7 to 10 business days (Monday to Friday, excluding bank holidays) from the date of your order for it to reach you. Tracking details are emailed on dispatch. UK delivery only.
You have 30 days from receiving your order to cancel it for any reason, then 14 days to send it back unused and in its original packaging. Faulty, damaged or incorrect items are replaced or refunded and we cover reasonable return postage. Refunds go back to your original payment method within 14 days of receiving the return.
7 to 10 business days from the date of your order. Every order is sent Royal Mail Tracked for a flat £5 and you receive tracking details by email when it is dispatched.
Yes. We list only genuine parts and optics from the brands shown, ordered in from the manufacturer for your order.
Compatibility notes on this page come from the manufacturer. If you are unsure, email us with your make and model before ordering and we will check rather than guess.
Yes. Bundle & Save applies automatically in your basket: 5% off when you buy 2 items, 10% off at 3 items and 15% off at 4 or more. It works across the whole range, so you can mix and match, and there is no code to enter.
Yes — you have 30 days from delivery to cancel for any reason, as long as the item is unused and in its original packaging. See our returns policy for the details.
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