Lens filter step-down adapter B&W 1102875 77mm to 72mm (thread reducer)

B&W 1102875 is a metal step-down lens filter adapter designed to reduce a lens front thread from 77mm to 72mm. It permits attachment of 72mm filters and accessories to lenses with a 77mm filter thread, providing a compact and durable solution for adapting filter sizes without changing the lens. The adapter maintains a slim profile to minimize vignetting on wide-angle lenses while offering a secure threaded connection for common photographic filters.

Advantages

This thread reducer allows photographers to use existing 72mm filters on lenses with larger 77mm threads, avoiding the need to purchase duplicate filters. Constructed from metal for reliable mechanical strength, the adapter offers stable, concentric threading to ensure alignment and reduce the risk of cross-threading. Its low-profile design helps limit vignetting when used with wide-angle glass, and the simple screw-on interface makes attachment and removal rapid and tool-free.

Suitable for

• Photographers who own lenses with a 77mm front thread and 72mm filters
• Situations requiring sharing of filters between camera bodies or lenses
• Fieldwork where minimizing carried gear is important
• Attaching 72mm screw-in accessories such as step-up rings, lens caps, or protective filters

Key specifications

• Material: metal construction for durability and precise threading
• Thread conversion: female 77mm to male 72mm
• Profile: low-profile design to reduce risk of vignetting on wider focal lengths
• Finish: machined surface to provide secure grip and accurate fit
• Compatibility: fits lenses with 77mm filter thread and accepts 72mm screw-in filters and accessories

How to use

Screw the adapter onto the lens front by engaging the 77mm female thread and turning clockwise until hand-tight. Then screw the 72mm filter or accessory into the adapter’s male thread until secure. For removal, reverse the process by unscrewing the filter first and then the adapter from the lens. Ensure threads are clean and free of grit before mounting to prevent cross-threading and to maintain smooth operation.

Usage recommendations

Use the adapter on lenses with moderate to longer focal lengths where the low-profile design reduces the chance of vignetting. Avoid stacking multiple adapters or thick filters on wide-angle lenses to prevent darkening of corners. Regularly inspect and clean threads to ensure reliable attachment and protect filter glass with caps when not in use.