Reptilia DOT Optic Mount Lower 1/3 1.54" for Trijicon MRO
Mix and match across the range: 2 items save 5%, 3 save 10%, 4 or more save 15% on your whole basket.
Fits the Trijicon MRO only, on any M1913 Picatinny rail. Fixed 39mm (1.54in) lower 1/3 bore height, not adjustable. Will not accept Aimpoint Micro, Aimpoint ACRO, Trijicon RMR or Holosun 509T optics. Mounting screws and hex L-key included.
Not sure it fits your rifle? Ask us before you order
The Reptilia DOT Mount is a one-piece Picatinny optic mount for the Trijicon MRO, holding the optic at Reptilia's 39mm lower 1/3 height, which the trade lists as 1.54in bore height.
The MRO at the classic co-witness height, on 43 g of billet aluminium with nothing in it that adjusts.
Machined from billet 7075-T6 aluminium with a Milspec Type III hard anodised finish, the DOT Mount attaches to any M1913 Picatinny rail and offers lower 1/3 co-witness with standard AR-15 back-up iron sights. Its spring-loaded nitrided steel clamp and mounting bolt sit flush with the body of the mount for a low-profile, anti-snag design, and mounting screws and a hex L-key are included.
39mm is Reptilia's own figure and comes out at 1.535in, which is why dealers list it as 1.54in bore height — the same mount, quoted two ways. At that height the MRO's large window sits over your irons rather than in front of them, so a UK straight-pull AR-15 keeps a usable backup without a taller mount and a taller cheek weld. Made in the USA.
Fits the Trijicon MRO, on any M1913 Picatinny rail including the flat-top upper of a UK straight-pull AR-15. Footprint and height are both fixed: MRO footprint, Reptilia 39mm (1.54in) lower 1/3 height. If you want the head-up sightline instead, the 1.93in MRO DOT Mount is the same footprint at the taller height. An Aimpoint Micro, ACRO or RMR uses a different pattern and will not fit this mount.
| Platform | AR-15 / M4 |
|---|---|
| Fits | Trijicon MRO, on any M1913 Picatinny rail |
| Type | One-piece red dot mount — 39mm (1.54in) lower 1/3 bore height |
| Material | Billet 7075-T6 aluminium; nitrided steel clamp |
| Finish | Milspec Type III hard anodised — Black Anodized |
| Weight | 43 g (1.5 oz) |
| Mount interface | Spring-loaded clamp to M1913 Picatinny |
| Made in | USA |
| Brand | Reptilia |
| MPN | 100-022 |
Big window, low sightline, irons still in the picture. Order the Lower 1/3 DOT Mount for Trijicon MRO 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: AR-15 Parts & Accessories, Scope Mounts & Optic Risers or browse all Reptilia.
| Platform | AR-15 / M4 |
|---|---|
| Fits | Trijicon MRO, on any M1913 Picatinny rail |
| Type | One-piece red dot mount — 39mm (1.54in) lower 1/3 bore height |
| Material | Billet 7075-T6 aluminium; nitrided steel clamp |
| Finish | Milspec Type III hard anodised — Black Anodized |
| Weight | 43 g (1.5 oz) |
| Mount interface | Spring-loaded clamp to M1913 Picatinny |
| Made in | USA |
| Brand | Reptilia |
| MPN | 100-022 |
| Category | Optic Mount |
| Barcode | 850002688337 |
£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.
39mm is Reptilia's published figure and equals 1.535in, which UK and US dealers both round to 1.54in bore height. It is the lower 1/3 co-witness position: standard AR-15 back-up iron sights appear in the bottom third of the optic window instead of across the centre of it.
Same footprint, different height, and neither converts into the other. This is the lower one, for a conventional cheek weld and a co-witness. The <a href="/products/reptilia-dot-mount-trijicon-mro-1-93">1.93in version</a> raises the sightline for a head-up position, a helmet or night vision. Choose on height, since the optic interface is identical.
Not in this listing. Reptilia's lower 1/3 MRO mount is stocked here in Black Anodized only. The 1.93in MRO mount is available in both Black Anodized and Flat Dark Earth Anodized if colour matters more to you than height.
The mount, its mounting screws and a hex L-key. Fit it firmly with the supplied key, check by hand that the mount does not move on the rail, and confirm your zero after the first range session as you would with any mount that has just gone on.
Optic mounts are sent from the United Kingdom with £5 tracked UK delivery in 7–10 business days, and you'll get tracking by email when it ships. If a part turns out to be the wrong fit, see our returns policy or <a href="/pages/contact">contact us</a> and we'll help sort it.
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.
Why Onyx Armaments
