Technical specifications

Values are transcribed from the BD500A1 controlled user manual, revision v5 dated 18 October 2026. Conditions and footnotes are retained. This page is a product reference, not an independent test report or certification.

Optical

Parameter	Value	Condition / note
Magnification	1×	True 1× optical system; no target magnification
Window size	32 × 26 mm (1.26 × 1.0 in)	Waveguide window
Parallax	Parallax-free	As stated in the supplied manual
Eye relief	Unlimited	Both-eyes-open aiming
Reticle	Red; 7 selectable types	Last reticle retained after power-off
Forward emission	Zero	Reticle routed internally; no forward reticle glow

Power and electronics

Parameter	Value	Condition / note
Battery	1 × CR123A (3.7 V, rechargeable)	Use only the supplied charger with the supplied rechargeable cells
Runtime	≥ 1,500 h at 22 °C	Actual runtime depends on brightness setting and ambient temperature
Daylight brightness	20 levels (manual) + Auto	Auto sets brightness to ambient light
Night-vision brightness	10 levels (manual)	For use with compatible night-vision equipment
Motion wake	Yes — motion sensor; 10-minute standby	Auto power-off after 8 h in standby
Low-battery alert	Reticle flashes every 2 s below 1 %	Replace or recharge promptly

Mechanical

Parameter	Value	Condition / note
Housing material	AL7075-T6 aluminium	—
Click value	0.5 MOA	Windage and elevation
Adjustment range	± 50 MOA windage and elevation	—
Mount	Quick-detach; lower 1/3 co-witness (1.65 in)	—
Rail standard	MIL-STD-1913 Picatinny / STANAG 2324	—

Physical and environmental

Parameter	Value	Condition / note
Dimensions	85 × 50 × 65 mm (3.3 × 2.0 × 2.6 in)	Axis order and measurement boundary are not stated in the source
Weight	280 g (9.9 oz)	Battery/accessory inclusion is not stated
Operating temperature	−30 °C to +60 °C (−22 °F to +140 °F)	—
Waterproof rating	IP67	Manufacturer-stated rating; see the IP-code note below
Recoil rating	1,200 G	Recoil tested with .338 Win Mag, .300 WM and 12 gauge per the manual

BD500A1 at a glance

The BD500A1 is a true 1× optical waveguide sight built for rapid, both-eyes-open target acquisition. A laser diode and a collimating lens generate the reticle inside the housing; an internal waveguide lens routes the reticle image to the shooter’s eye. Because the reticle is never projected onto the outward-facing window, the sight has zero forward reticle emission — there is no visible reticle glow toward the target.

The 32 × 26 mm waveguide window is parallax-free and gives unlimited eye relief. Seven selectable reticles, 20 daylight brightness levels with automatic brightness, 10 night-vision levels and motion-activated wake-up cover a wide range of light conditions. A single rechargeable CR123A cell provides at least 1,500 hours of operation at 22 °C. The AL7075-T6 aluminium housing is stated as IP67 and rated for 1,200 G recoil, and the quick-detach mount provides a lower 1/3 co-witness on MIL-STD-1913 Picatinny and STANAG 2324 rails.

The BD500A1 is an aiming aid for close- to medium-range use on rifles, carbines, shotguns and other 1913-rail platforms. It does not magnify the target and does not replace safe firearm handling, marksmanship training or the user’s responsibility to comply with local law.

Key features

• Optical waveguide with zero forward emission. The reticle is routed internally to the eye, so no reticle light leaves the front of the sight.
• Parallax-free, unlimited eye relief. The reticle remains aligned with the point of aim as the eye moves within the window.
• Seven reticles, retained after power-off.
• 20 daylight levels plus Auto, and 10 night-vision levels.
• Motion wake-up from standby and automatic power-off after 8 hours in standby.
• At least 1,500 hours of runtime at 22 °C from one CR123A cell (brightness- and temperature-dependent).
• AL7075-T6 aluminium housing, stated IP67, rated for 1,200 G recoil.
• Quick-detach lower 1/3 co-witness mount for MIL-STD-1913 and STANAG 2324 rails (1.65 in).
• High colour fidelity and astigmatism-friendly reticle compared with a projected red dot, because the window does not tint the scene.
• Compatible with night-vision devices, thermal optics and magnifiers according to the supplied model document.

How the optical waveguide works

A conventional red-dot sight projects an LED reticle onto a semi-reflective lens, so part of the reticle light leaves the front of the sight. A holographic sight reconstructs a hologram in front of the window. The BD500A1 uses a third approach: the reticle is generated inside the housing and routed to the eye through an optical waveguide.

The internal path runs from the laser diode through the collimating lens to the waveguide lens, which directs the reticle image to the eye. The waveguide keeps the reticle aligned with the eye across the window and produces a flat, high-contrast image. Because no reticle light is projected forward from the objective, the sight has no forward light signature. The window itself does not tint the scene, which helps preserve natural target colours.

These are descriptions of the product’s stated optical architecture. They are not a measurement of parallax, distortion, transmission or aiming accuracy beyond the values in the model document.

Performance conditions and limits

• Runtime is quoted at 22 °C and depends on brightness setting and ambient temperature. Cold conditions and high brightness reduce runtime.
• Parallax-free is the model’s stated optical behaviour. It does not remove the need to confirm zero on the host platform.
• IP67 is a manufacturer-stated ingress rating. IEC 60529 defines the IP code; citing the standard does not certify this product. IP67 is not a diving or high-pressure-washing rating.
• 1,200 G recoil is a stated rating with the listed test calibres. It is not a guarantee for every host, mount, ammunition load or installation.
• Zero retention after removal, impact or mount changes must be confirmed on the host; the supplied manual describes the inspection and adjustment process.
• Night-vision compatibility depends on the night-vision device, its gain and the selected brightness level. Confirm compatibility in the intended configuration.
• No forward reticle emission is a property of the reticle path. It does not make the sight invisible to all detectors and does not replace tactical light discipline.

Intended use and application scenarios

The BD500A1 is intended for close- to medium-range aiming on rifles, carbines, shotguns and other platforms fitted with a MIL-STD-1913 / Picatinny or STANAG 2324 rail. It is an aiming aid only: it does not magnify, it does not illuminate the target and it does not replace safe firearm handling.

• Both-eyes-open close-range aiming. The unlimited eye relief and parallax-free window support fast target acquisition with both eyes open.
• Day and night-vision use. Twenty daylight levels plus Auto and ten night-vision levels allow the reticle to be matched to ambient light and compatible night-vision equipment.
• Rifle, carbine and shotgun platforms. The quick-detach lower 1/3 co-witness mount suits 1913-pattern hosts and supports use with magnifiers and thermal clip-ons according to the supplied document.
• Sport shooting, hunting where lawful, training and professional use. The product is a firearm accessory; the buyer and user are responsible for compliance with all applicable laws governing purchase, possession, transport and use.
• Low-signature observation of the aiming point. Because the reticle is not projected forward, the sight does not create a visible reticle glow toward the target.

Application examples describe configuration possibilities, not a guarantee of hit probability, legality in a particular jurisdiction or suitability for a specific host. Confirm local law and range rules before use.

Mounting, power and configuration

The sight installs on a MIL-STD-1913 / Picatinny or STANAG 2324 rail with its quick-detach mount. Confirm that the rail, mount and host are mechanically sound, that the mount is fully seated and locked, and that the sight cannot move by hand before use. The lower 1/3 co-witness height is 1.65 in; confirm compatibility with the host’s iron sights and any magnifier or clip-on.

Power is supplied by one rechargeable CR123A cell. Charge only the supplied rechargeable cells in the supplied charger; never place a primary (non-rechargeable) CR123A cell in the charger. The sight retains its last reticle and brightness setting after power-off. The supplied manual gives the complete button, reticle, zeroing and inspection procedure; this page intentionally does not reproduce operating instructions.

Night-vision devices, thermal optics and magnifiers are listed as compatible in the supplied document. Optical stacking can change eye relief, image brightness and zero; test the complete configuration before relying on it.

Care, storage and safety

• Clean exterior dust and dirt with a clean, soft, dry cotton cloth. Do not use chemical solvents or thinners on the housing.
• Avoid rubbing loose dust or sand across the glass. Use non-abrasive optical care materials; confirm coating compatibility before using any cleaning solvent.
• Store in a dry, well-ventilated place and remove the battery before a long period without use. A separate storage-temperature or humidity limit is not established by the supplied table.
• Do not disassemble, modify or attempt unauthorised repairs. Stop using a unit with visible cracks or damage and seek qualified service assessment.
• Before installing, adjusting or servicing the sight, make sure the firearm is unloaded, the chamber is empty and the muzzle is pointed in a safe direction. Wear eye protection when shooting.
• Do not use the sight to observe the Sun. NASA describes serious eye hazards when optics lack purpose-designed solar-viewing protection.
• Do not dispose of lithium cells with household waste; follow local recycling and disposal rules.