Irix IFH-100 Filter Holder Adapter Ring

The IFH-100 and IFH-100-PRO holders do not thread onto a lens directly. This ring does: it screws into the filter thread on the front of the lens and gives the holder something to clamp to. One ring per thread size, so a kit that spans several lenses needs one of each rather than a step-up stack that risks vignetting.

Nine sizes are offered here, 52 mm through 95 mm, all working with either the standard IFH-100 or the PRO holder and the 100 mm square filters that go in them.