Adjustable Iris Aperture Diaphragm Filter Pack M30 to M37 - NV Upgrade

In this review of the Adjustable Iris Aperture Diaphragm Filter Pack the bottom line is simple: this tiny adapter kit is aimed at users who need quick, reliable aperture control for night vision and small optics. It is best for technicians, hobbyists, and field users who work with PVS-14 style devices or lenses that accept M30 to M37 fittings, because the kit provides a compact, metal-built adjustable iris that ranges from 1.5mm to 26mm and improves control over exposure and depth of field. The review focuses on build, fit, and practical operation rather than specs alone.

Key Features

• Adjustable iris aperture: The kit covers mounting sizes M30 to M37 and gives a continuous aperture range from 1.5mm to 26mm so users can fine tune light admission precisely.
• Durable construction: Made from aviation metal, the diaphragm ring is built for rugged use and resists wear from repeated adjustments in the field.
• Simple operation: A dedicated handle lets the operator change the aperture diameter quickly and directly without tools, useful during rapid setup or in low light.
• Compatibility: Designed as a lens reversing adapter type, it is intended for PVS-14 night vision devices and similar equipment that accept M30-M37 adapters.
• Pack value: The product includes two adjustable aperture filters, which is convenient for users who need spares or want matched setups on two devices.

Who It's For

The diaphragm filter pack is well suited to users of legacy and modern night vision monoculars, especially those using PVS-14 style mounts, and to photographers or technicians who need a compact way to control aperture on small optics. People who value metal construction and a mechanical control over exposure will find the kit useful.

This is not aimed at casual camera buyers who expect electronic aperture control or plug-and-play compatibility with all lenses; anyone who needs motorized or camera-integrated aperture metering should look elsewhere. Also, if you require a broader range of thread sizes beyond M30-M37, a different adapter solution will be needed.

Pros & Cons

Pros

• Quality metal build delivers solid durability and a reassuring feel during adjustment.
• Wide aperture range from 1.5mm to 26mm gives precise control of light and depth of field for small optics.
• Includes two identical adjustable filters, offering immediate redundancy or multi-device use.

Cons

• Some users report mixed rotation feel and occasional engagement issues with the iris, so adjustment may not be perfectly smooth for every unit.
• Limited to M30-M37 sizes, so it will not fit lenses outside that thread range without additional adapters.

Specifications

Our Verdict

The Folisobo Adjustable Iris Filter Pack is a practical, value-minded upgrade for PVS-14 users and anyone needing manual aperture control on small optics. Its metal construction and broad 1.5-26mm range make it a durable, flexible choice, though buyers should expect occasional variability in rotation feel. For field use or matched dual setups it represents good value and straightforward performance.

Frequently Asked Questions

Will this fit my night vision monocular?
It fits devices and lenses that accept M30 to M37 thread sizes, including PVS-14 style mounts; check your device thread before buying.

How is the aperture adjusted?
The diaphragm is adjusted manually using the attached handle, giving direct mechanical control from 1.5mm to 26mm.

How many filters are included?
The package includes two adjustable aperture filters, allowing for spare use or dual-device installation.