Lens Adapter Ring Sony ALC-F405S for 40.5mm Filters — Sony ALCF405S

Sony ALC-F405S is a lens adapter ring that enables attachment of 40.5 mm screw-in filters to compatible Sony lenses. The adapter provides a threaded interface that matches 40.5 mm filters, maintaining correct alignment and a secure connection between filter and lens. It is intended for use with lenses that accept external adapter rings of this size and is compatible with common filter types such as neutral density, polarizing and UV screw-on filters.

Advantages

The adapter ring offers a precise, threaded mount that reduces play and wobble when a 40.5 mm filter is attached. Made to fit the optical and mechanical profile of compatible Sony lenses, it preserves front element access and filter functionality without altering focal properties. The compact, lightweight construction adds minimal bulk and weight, making it practical for handheld, travel and field photography.

Suitable for

• Attaching 40.5 mm neutral density filters for long exposures and exposure control
• Using 40.5 mm circular polarizers to reduce reflections and enhance color saturation
• Protecting the front element with 40.5 mm UV or clear protective filters during travel or outdoor shoots
• Compact lens setups such as retractable zooms where space and weight are limited

Key specifications

• Filter thread: 40.5 mm screw-in
• Function: adapter ring to accept 40.5 mm filters on compatible lenses
• Compatibility: designed for use with Sony lenses that accept external 40.5 mm threaded adapters
• Construction: low-profile, lightweight metal/plastic composite suitable for mounting on small front elements

How to use

To use the adapter ring, align it with the lens front where the lens accepts external adapter rings and carefully screw it onto the lens until it seats securely without cross-threading. Once the adapter is mounted, thread the 40.5 mm filter into the adapter until finger-tight; avoid over-tightening. For removal, unscrew the filter first and then the adapter from the lens. Ensure threads are clean and free of debris before mounting to prevent damage to the filter or lens.

Usage recommendations

Regularly inspect the adapter and filter threads for dirt and grit; clean with a soft brush or compressed air and a microfiber cloth to maintain smooth operation. When using heavy filters or filter stacks, support the lens to avoid placing excessive strain on the adapter connection.