Magpul MBUS 3 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 1913 Picatinny top rails on AR-15/M4 pattern rifles. Pairs with the MBUS 3 Rear (MAG1167).
Not sure it fits your rifle? Ask us before you order
The Magpul MBUS 3 Front is a polymer flip-up backup iron sight for AR-15 and M4 rifles, clamping to any 1913 Picatinny top rail.
The third generation of one of the most widely used backup sights — stronger, slimmer and smoother than ever.
The Magpul MBUS 3 Front Sight (MAG1166) refines the polymer backup sight that armed a generation of rifles. The housing is strengthened against crush and impact, the profile is slimmed to reduce snags, and the spring-loaded deployment now runs on crisp constant tension — press the release and the sight snaps up positively, from either side, every time.
The detail shooters notice most: the MBUS 3's tool-less front post adjustment, which makes zeroing dramatically quicker than wrestling with a legacy A2-style post tool. Impact-resistant polymer keeps weight and cost down while shrugging off the daily knocks of training — the pragmatic backup for optics-first builds.
Fits 1913 Picatinny top rails on AR-15/M4 pattern rifles, so you need a continuous or front rail section at the gas block or handguard end. Check that your rail height at the front matches the rear sight position you plan to use. Pair it with the MBUS 3 Rear (MAG1167) for a matched, ambidextrous backup system.
| Platform | AR-15 / M4 |
|---|---|
| Type | Flip-up front backup sight |
| Material | Reinforced polymer |
| Finish | Black, Flat Dark Earth, Olive Drab Green |
| Mount interface | 1913 Picatinny top rail |
| Adjustment | Tool-less elevation |
| Brand | Magpul Industries |
| MPN | MAG1166-BLK · MAG1166-FDE · MAG1166-ODG |
The proven backup, perfected. Order the MBUS 3 Front 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 | Flip-up front backup sight |
| Material | Reinforced polymer |
| Finish | Black, Flat Dark Earth, Olive Drab Green |
| Mount interface | 1913 Picatinny top rail |
| Adjustment | Tool-less elevation |
| Brand | Magpul Industries |
| MPN | MAG1166-BLK · MAG1166-FDE · MAG1166-ODG |
| Category | Iron Sights |
| Shipping weight | 0.3 kg |
| Barcode | 840815132165 |
£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 fits 1913 Picatinny top rails on AR-15/M4 pattern rifles, so you need a continuous or front rail section at the gas block or handguard end. It is designed to pair with the <a href="/products/magpul-mbus-3-sight-rear-mag1167">MBUS 3 Rear (MAG1167)</a>. Check that your rail height at the front matches the rear sight position you plan to use.
Elevation is tool-less, so you can zero the front post at the range without carrying a sight tool or a cartridge rim. That is the practical difference from older backup sights that need a tool to depress and rotate the post. It stays folded out of the way of an optic until you flip it up.
The MBUS 3 is reinforced polymer, which keeps weight down and allows the colour options, while the MBUS Pro line is steel and offered in black only. Both are backup sights for a Picatinny rail, so the choice is mostly about material, weight and finish. The original MBUS front is the earlier polymer generation if you want the lower-cost option. Our <a href="/blogs/buying-guides/magpul-mbus-3-vs-mbus-pro">MBUS 3 vs MBUS Pro guide</a> goes through it in more detail.
It is available in Black, Flat Dark Earth and Olive Drab Green. A front sight on its own is only half a sight picture, so you will want a matching rear unless your rifle already has one. Fitting is to the rail clamp screw, so a suitable driver is all that is usually needed.
Sights are dispatched from the United Kingdom with £5 tracked UK delivery in 7–10 business days and tracking comes by email when the parcel leaves. If the height or rail fit is not right for your build, 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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