New Products

Second Reef Releases Adapter for Bun-G-Ring

The solution enables mounting filters to lenses without matte boxes or tape.

ASC Staff

The Second Reef Bun-G-Ring Circular Glass Adapter enables mounting filters to lenses without matte boxes or tape.


The CGA-138 is designed to mount standard 138mm diopters, rota polas and other round optical elements directly onto a Bun-G-Ring via the bungee-cord mount system; it incorporates a spring and lock mechanism that ensures rock-solid mounting. Rectangular filters can be positioned either in front of the CGA-138 or between the CGA-138 and the Bun-G-Ring depending on magnification needs. If a single +3 diopter is not enough, multiple CGA-138s can be stacked.


The CGA-138 weighs 1.41 ounces and functions only with the Bun-G-Ring. It is not a standalone product.


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