Holosun Lower 1/3 Co-Witness Dot Sight Mount with Quick Detatch Attachment
The Holosun Lower 1/3 Co-Witness QD Mount is a simple but solid upgrade if you want a reliable way to run your red dot at the right height and still keep backup irons in the picture. It’s built for micro red dots and gives you that lower 1/3 co-witness setup, so your irons sit in the lower part of the window while the dot stays clean and unobstructed up top. The quick detach lever is the real bonus—you can pop the optic on or off fast without tools, and it’ll return to zero when you remount it. Made from tough aluminum with a compact, lightweight design, it’s basically a “fit it once and forget it” mount that keeps your setup flexible without messing up consistency.
-Nathan (Technical Advisor)
Engineered for tactical efficiency and rapid deployment, the Holosun HSCQD1 Red Dot Sight Mount offers shooters a robust and reliable mounting solution for their optics. Designed specifically for use with Holosun T1 Red Dot Sights, this mount is compatible with Picatinny, M1913, and Weaver rails, making it an ideal fit for a wide range of rifles and shotguns.
Crafted from durable 6061 T6 aluminium, the mount features a hard anodised, corrosion-resistant finish that stands up to the rigours of heavy use in demanding environments. Whether you're on the range or in the field, its rugged construction ensures long-lasting performance and consistent alignment.
One of the standout features is the Quick Detach (QD) lever, allowing you to effortlessly attach or remove your optic without tools. This is particularly useful for shooters who need to switch configurations quickly or store their optics separately from the firearm.
The mount includes a spacer to provide a lower 1/3 co-witness height, enabling effective use of backup iron sights in conjunction with your red dot. This setup delivers a clear and unobstructed sight picture, giving you faster target acquisition and improved shooting confidence.
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Mounting Method: Quick Detach (QD) lever
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Material: 6061 T6 aluminium
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Finish: Hard anodised, matte black (corrosion-resistant)
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Rail Compatibility:
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Picatinny (MIL-STD-1913)
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Weaver
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M1913
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Co-Witness Height: Lower 1/3 co-witness (with included spacer)
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Optic Compatibility:
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Holosun T1 Red Dot Sight
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Holosun 503 series
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Holosun 403 series
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Aimpoint T1 footprint and similar micro dot sights
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Firearm Compatibility: Rifles and shotguns
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Included Accessories:
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1x Co-witness spacer
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4x Installation screws
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1x Allen wrench
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Dimensions:
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Length: 48mm
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Width: 27mm
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Height: 30mm
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Colour: Black
- 6061 T6 aluminium construction for strength and durability
- Hard anodised black finish for enhanced corrosion resistance
- Quick Detach lever for fast, tool-free mounting
- Lower 1/3 co-witness compatibility with Holosun 503 and 403 series optics
- Spacer, four installation screws, and Allen wrench included
- Holosun Lower 1/3 Co-Witness Dot Sight Mount with Quick Detatch Attachment
- 1x Co-witness spacer
- 4x Installation screws
- 1x Allen wrench
1. What does lower 1/3 co-witness mean?
It means your iron sights sit in the bottom third of the optic window, while the red dot stays above them for a less cluttered view.
2. What is a QD mount?
QD stands for Quick Detach—it lets you attach or remove the optic without tools in seconds.
3. Will it keep zero after removing it?
Yes, good QD mounts are designed to return to the same position with consistent zero when reattached.
4. What optics does it fit?
It’s made for Aimpoint Micro-style footprints, which includes many Holosun micro red dots.
5. What rail does it use?
It attaches to standard Picatinny (MIL-STD-1913) and similar rails.
6. What material is it made from?
Typically 6061-T6 aluminum with a hard anodized finish for durability and corrosion resistance.
7. Does it need tools to install?
No, the QD lever system is designed for tool-free mounting and removal.
8. Why use lower 1/3 instead of absolute co-witness?
It gives a cleaner sight picture since the irons sit lower in the window instead of blocking the center view.
9. Is it heavy?
No, it’s designed to be lightweight while still strong enough for recoil and hard use.
10. What’s the main benefit of this mount?
It makes swapping or removing your optic quick and easy while keeping your setup consistent, properly aligned, and compatible with backup iron sights.
Tactical Scope Shipping Policy
Our aim is to ensure that your order arrives with you as soon as possible and in the safest, most cost-effective means.
Shipping charges may be subject to additional surcharges if out of area or over weight restrictions.
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Couriers
We use DPD, Royal Mail, TNT, and UPS courier services for all our UK and international orders. Once your order is dispatched, you will receive an email with your unique tracking number.
In-Store Items
These are items we have in stock and aim to dispatch within 1–2 working days. During busy periods, this may be delayed slightly. If you'd prefer to collect your item in person, please contact us in advance to arrange. Collection orders must be paid for beforehand.
Pre-Order Items
Pre-order items are typically out-of-stock or in limited supply. Purchasing a pre-order secures your item, and it will be dispatched within 24 hours of restock where possible. Check the product page for estimated restock dates. These dates may change, so staying in touch is advised.
International Delivery & Taxes
If your shipping address is outside the UK, you may incur import duties or taxes upon arrival in your country. These charges are your responsibility. Customs regulations vary, so please check with your local customs office. Some packages may be opened for inspection.
Need Help?
If you need assistance, call us at +44 (0)1803 611895 (Optics Warehouse) or email [email protected].
DPD Shipments & PIN Code Delivery
We have now introduced DPD Pin Code verification for all orders shipped via DPD. You will receive a PIN via email and text.
A valid email and mobile number must be provided at checkout. Emails will come from Riviera House 3PL. Please check spam/junk folders if not received.
Failure to present your PIN to the delivery driver will result in a failed delivery and rescheduling may be required.