Lens filter step-down adapter B+W 49mm to 43mm model 1102853 (49→43)

The Lens filter step-down adapter B+W 49mm to 43mm model 1102853 (49→43) is a precision accessory that allows photographers and videographers to mount 43mm filters or accessories on lenses with a 49mm front thread. Designed as a filter reducer, the adapter provides a reliable mechanical connection between a larger lens thread and a smaller filter diameter, enabling use of existing 43mm glass, slim filters, or accessories without changing the lens.

Advantages

Constructed from machined metal, this B+W step-down adapter offers durable, lightweight performance with accurate thread alignment to minimize wobbles and ensure stable attachment. The adapter preserves access to the lens front while allowing the use of smaller-diameter filters, reducing the need to buy duplicate filters when switching lenses. Its simple screw-on design makes it straightforward to install and remove.

Suitable for

• Attaching 43mm screw-in filters to lenses with 49mm filter threads
• Using slim or specialty 43mm filters when a 49mm lens is in use
• Photographic and video setups requiring filter size conversion

Key specifications

• Thread conversion: 49mm (lens) to 43mm (filter)
• Material: machined metal construction
• Mount type: screw-in (male to female thread reducer)
• Compatibility: fits lenses with 49mm front thread and 43mm screw-in filters

How to use

Align the adapter’s 49mm female thread with the lens’s 49mm front thread and carefully screw the adapter onto the lens until secure, avoiding cross-threading. Then attach the 43mm filter or accessory by screwing it into the adapter’s 43mm thread until it is snug. To remove, reverse the process: unscrew the filter first, then the adapter from the lens. Check thread alignment visually before applying force to prevent damage.

Usage recommendations

Use the adapter with slim or low-profile 43mm filters to reduce the risk of vignetting on wide-angle lenses. Keep threads clean and free of grit, and avoid overtightening to maintain thread integrity and ensure easy removal.