380 rear sight selections analyzed across 12+ brands

AR15 Rear Sight Guide: What 15,000+ Builders Choose

GGPP Editorial Team·March 23, 2026·5 min read
AR-15OpticsBuyer's Guide

Quick Answer: What Rear Sight Do Builders Choose?

Magpul dominates at 30.2% combined (MBUS Gen 2 26.3%, MBUS Pro 3.9%). The MBUS Gen 2 Rear is the single most-selected individual sight in our database. Ultradyne C4 at 12.4% leads the offset segment.

  • Most Popular: Magpul MBUS Gen 2 Rear Black at 26.3%
  • Best Offset: Ultradyne C4 Offset Folding at 12.4%
  • Best Budget: MFT Flip Up Polymer Black at 9.2%
  • Best Night Sight: Troy Industries Tritium at 5.0%
15K+
Builds Analyzed
380
Rear Sight Selections
52+
Unique Products
12+
Brands Tracked
DATA BEHIND THIS GUIDE
MetricValue
Builds Analyzed15K+
Rear Sight Selections380
Unique Products52+
Brands Tracked12+

Most Selected Rear Sights

% of qualified builds with a rear sight selection

Most Selected Rear Sights
ItemShare (%)
Magpul MBUS Gen 2 Rear Black26.3%
Ultradyne C4 Offset Folding12.4%
MFT Flip Up Polymer Black9.2%
Wilson Combat Flip-Up Bus6.6%
Troy Industries Tritium5%
Magpul MBUS Pro Rear3.9%

Brand Breakdown

Magpul at 30.2% combined dominates rear sights. The MBUS Gen 2 at 26.3% is the default backup rear sight. The MBUS Pro at 3.9% is the steel upgrade. Ultradyne at 12.4% offers a unique offset folding design for builds with magnified primary optics. MFT at 9.2% is the budget polymer alternative to Magpul. Wilson Combat at 6.6% brings a metal flip-up bus sight. Troy Industries at 5.0% offers tritium night sights for low-light use.

Pair your rear sight with a matching front sight for consistent co-witness height. The Magpul MBUS Gen 2 Rear at 26.3% pairs with the MBUS Gen 2 Front (13.3% of front sight selections). Mismatched heights create zeroing issues.

How to Choose

  1. Budget (Under $30): MFT Flip Up Polymer. Basic polymer backup.
  2. Standard ($30-$50): Magpul MBUS Gen 2. The default. 26.3% of builders agree.
  3. Metal ($50-$80): Wilson Combat or Magpul MBUS Pro. Steel construction for durability.
  4. Night Sight ($80+): Troy Industries Tritium. Visible in low light without batteries.

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Frequently Asked Questions

Magpul MBUS Gen 2 Rear Black leads at 26.3% of all rear sight selections. It is the standard backup rear sight. Over one in four rear sight purchases is this specific Magpul model.
Some builders already have a front sight (from an A-frame gas block or previous purchase) and only need a rear. Others want to mix brands, pairing a Magpul rear with a different front sight. Individual rear sights at 380 selections complement the 1,140 set selections in our Iron Sights data.
Flip-up is the standard for backup sights on optic-equipped rifles. The Magpul MBUS at 26.3% folds flat. Fixed rear sights are for builds without a primary optic, or for maximum durability (Troy, Daniel Defense fixed sights).
GPP

GPP Editorial Team

AR Build Specialists

GunPartPicker guides are powered by data from real builds — what builders actually select tells the story.

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