The Holosun HS403C + HM3X combo is a great-value complete rifle setup — the proven 20mm micro red dot with Solar Failsafe plus the 3x flip-to-side magnifier, matched and ready to mount.
The HS403C runs a crisp 2 MOA red dot with solar backup, Shake Awake and up to 50,000 hours from a CR2032, shipping with both absolute and lower-1/3 mounts. The HM3X adds 3x with 2.75in eye relief, adjustable diopter and an ambidextrous QD flip mount with co-witness spacer. Both IP67, 6061-T6 aluminium.
How It Compares
Want an enclosed emitter? The ARO + HM3X combo. Bigger window? The HS510C + HM3X. Browse all rifle red dots and magnifiers; read our magnifier guide.
Ideal For
- AR-15s and carbines on a budget
- First red dot + magnifier setup
- Lightweight micro-dot builds
Key Features
- HS403C — 2 MOA red dot, Solar Failsafe, 20mm micro
- HM3X 3x flip-to-side QD magnifier
- Absolute + lower-1/3 mounts included (both units)
- Shake Awake; up to 50,000 h (CR2032)
- IP67; 6061-T6 aluminium
Technical Specifications
| Red Dot |
HS403C — 2 MOA red, solar + battery, 12 settings |
| Magnifier |
HM3X — 3x, 2.75in eye relief, ±diopter |
| Battery |
CR2032 — up to 50,000 h + Solar Failsafe |
| Mounts |
Absolute + lower-1/3 (dot); QD flip + spacer (mag) |
| Durability |
6061-T6; IP67 (both units) |
| MPN / UPC |
HS403C-HM3X / 810047071624 |
What's Included
- Holosun HS403C red dot + HM3X magnifier
- Absolute + lower-1/3 mounts, spacer, CR2032, tools, lens cloths, manuals
UK Delivery & Support
UK-stocked and dispatched tracked from our UK warehouse — no import duties or customs delays — backed by UK-based support and Holosun's warranty.
Frequently Asked Questions
What is Solar Failsafe?
A solar panel that powers the dot in bright light and backs up the battery — the optic keeps running even with a dead cell in daylight.
Do the heights match?
Yes — both include lower-1/3 and absolute options, so the pair lines up at either height.
Can I remove the magnifier?
Yes — the QD lever detaches it in seconds, or flip it aside for 1x.
