Magpul MBUS Pro Rear Folding Sight
Mix and match across the range: 2 items save 5%, 3 save 10%, 4 or more save 15% on your whole basket.
Fits 1913 Picatinny top rails on AR-15/M4 pattern rifles. Pairs with any MBUS Pro front sight.
Not sure it fits your rifle? Ask us before you order
The Magpul MBUS Pro Rear is an all-steel dual-aperture folding backup iron sight for AR-15 and M4 rifles, clamping to any 1913 Picatinny top rail.
A steel rear sight with dual apertures and tool-less windage — the MBUS Pro Rear completes a backup system you can actually rely on.
The Magpul MBUS Pro Rear Sight (MAG276) brings all-steel construction to the rear half of your iron-sight equation. The dual-aperture design flips between a large ring for fast, close work and a small aperture for precision at distance — the classic combat configuration, executed with machined precision. Windage adjusts tool-lessly with positive, audible clicks, so refining zero at the range needs nothing but your fingers.
Folded, the sight sits extraordinarily low and snag-free; deployed, it locks up without play and returns to zero shot after shot. Paired with an MBUS Pro front, you get a sighting system tough enough to serve as primary irons on a dedicated build — and dependable enough to bet on when an optic goes down.
Fits 1913 Picatinny top rails on AR-15/M4 pattern rifles, at the rear of the receiver rail in the usual backup sight position. Make sure there is clear rail behind your optic or mount before ordering, and that the front and rear sit on the same rail plane. It pairs with any MBUS Pro front sight; elevation is normally set on the front sight, so zero the pair together.
| Platform | AR-15 / M4 |
|---|---|
| Type | Dual-aperture flip-up rear sight |
| Material | Steel |
| Finish | Black |
| Mount interface | 1913 Picatinny top rail |
| Adjustment | Tool-less windage |
| Brand | Magpul Industries |
| MPN | MAG276 |
Finish the system properly. Order the MBUS Pro Rear 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: Iron Sights & Backup Sights, AR-15 Parts or browse all Magpul.
| Platform | AR-15 / M4 |
|---|---|
| Type | Dual-aperture flip-up rear sight |
| Material | Steel |
| Finish | Black |
| Mount interface | 1913 Picatinny top rail |
| Adjustment | Tool-less windage |
| Brand | Magpul Industries |
| MPN | MAG276 |
| Category | Iron Sights |
| Shipping weight | 0.4 kg |
| Barcode | 873750008387 |
£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.
It mounts to 1913 Picatinny top rails on AR-15/M4 pattern rifles, at the rear of the receiver rail in the usual backup sight position. It pairs with any MBUS Pro front sight, for example the <a href="/products/magpul-mbus-pro-front-folding-sight">MBUS Pro Front Folding Sight</a>. Make sure there is clear rail behind your optic or mount before ordering.
The MAG276 gives you two apertures: a larger one for quick, close work and a smaller one for a more precise sight picture at distance. You switch between them by flipping the aperture over. That is the main difference from single-aperture backups, and it is a genuine benefit if you use irons for more than emergencies.
Windage is tool-less, so it can be adjusted by hand at the range without carrying a sight tool. The sight body is steel throughout, which is why it feels dense compared with a polymer flip-up. Elevation is normally set on the front sight, so plan on zeroing the pair together.
You need a matching MBUS Pro front sight, and the front and rear should sit on the same rail plane so the sight picture lines up. The MBUS Pro line is black steel only, so there is no colour to choose; the polymer MBUS rear is the lighter alternative. The wider range is in <a href="/collections/magpul-mbus-sights-backup-iron-sights">Magpul MBUS sights</a>.
This sight goes out from the United Kingdom with £5 tracked UK delivery in 7–10 business days and tracking is emailed at dispatch. If it does not work with your optic or rail height, 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.
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