Magpul MBUS Sight Front for AR-15/M4
Mix and match across the range: 2 items save 5%, 3 save 10%, 4 or more save 15% on your whole basket.
Fits any MIL-STD-1913 Picatinny rail, including flat-top uppers and railed gas blocks. Pair with the MBUS rear sight for a full set.
Not sure it fits your rifle? Ask us before you order
The Magpul MBUS Front is a folding polymer back-up iron sight for AR-15 and M4 rifles, clamping to any MIL-STD-1913 Picatinny rail.
Rugged, low-cost backup iron sights that stay out of the way until you need them — the polymer standard for a reliable BUIS front.
The Magpul MBUS (Back-Up Sight, MAG247) front folds flat against the rail to clear your optic, then springs up positively at the push of a button when you need irons. Moulded from impact-resistant polymer over a steel-reinforced core, it shrugs off knocks that would bend aluminium sights while adding almost no weight to the rifle.
The front sight post is fully adjustable for elevation with the same tool used on standard A2 front sights, so zeroing is familiar and quick. It is the sensible, affordable insurance every optic-equipped carbine should carry.
Clamps to any MIL-STD-1913 Picatinny rail on AR-15/M4 pattern rifles, including flat-top uppers and railed gas blocks. You need enough clear rail at the front and the right height relationship with your rear sight. Pair it with the MBUS rear (MAG248) for a complete folding sight set; front-post elevation is set with a standard A2 sight tool.
| Platform | AR-15 / M4 |
|---|---|
| Type | Folding back-up front sight (BUIS) |
| Material | Impact-resistant polymer over a steel-reinforced core |
| Finish | Black, Flat Dark Earth, Stealth Gray, Olive Drab Green |
| Mount interface | Picatinny / MIL-STD-1913 |
| Adjustment | Elevation (A2-standard front post) |
| Brand | Magpul Industries |
| MPN | MAG247-BLK · MAG247-FDE · MAG247-GRY · MAG247-ODG |
Affordable insurance for an optic-equipped carbine. Order the MBUS Front Sight 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 | Folding back-up front sight (BUIS) |
| Material | Impact-resistant polymer over a steel-reinforced core |
| Finish | Black, Flat Dark Earth, Stealth Gray, Olive Drab Green |
| Mount interface | Picatinny / MIL-STD-1913 |
| Adjustment | Elevation (A2-standard front post) |
| Brand | Magpul Industries |
| MPN | MAG247-BLK · MAG247-FDE · MAG247-GRY · MAG247-ODG |
| Category | Iron Sights |
| Shipping weight | 0.1 kg |
| Barcode | 873750004310 |
£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 clamps to any MIL-STD-1913 Picatinny rail on an AR-15/M4 pattern rifle, which covers flat-top uppers and railed gas blocks. Check you have enough clear rail at the front once your optic and any light mount are in place, and that the height relationship with your rear sight works. If your handguard is M-LOK with no rail at the front, you will need a rail section there first.
It sits folded flat against the rail so it does not obstruct your optic, then springs up positively at the push of a button when you need irons — an optic failure, a dead battery, or a close-quarters shot you would rather take on irons. The MBUS folds low enough to clear an optic and co-witness with most red dots. Being moulded polymer over a steel-reinforced core, it takes knocks that would bend an aluminium sight while adding almost no weight.
This original MBUS is the light, low-cost polymer option. The <a href="/products/magpul-mbus-3-sight-front-mag1166">MBUS 3</a> is the updated generation, while the <a href="/products/magpul-mbus-pro-front-folding-sight">MBUS Pro</a> is the all-steel version with a much slimmer folded profile for shooters who want metal. Our <a href="/blogs/buying-guides/magpul-mbus-3-vs-mbus-pro">MBUS 3 vs MBUS Pro comparison</a> goes through the differences, and there is more in <a href="/collections/iron-sights-backup-sights">Iron Sights & Backup Sights</a>.
Yes — the rail clamp and cross-bolt are integral, so you slide it on to the rail at the position you want and tighten the cross-bolt. Front-post elevation is set with a standard A2 front sight tool, exactly as on a fixed A2 sight, so zeroing is familiar. Pair it with the MBUS rear (MAG248) for a complete folding set, setting windage on the rear and elevation on the front.
Sights 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.
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