The multi-coated and low-profile Irix Edge ND128 95mm filter is designed specifically for the Irix 15mm f/2.4 lens.

A neutral density (ND) filter reduces the amount of light that enters the lens. An ND128 will darken the image by about 7 stops.
Usually, there is a shortage of light in photography, but sometimes there can be too much. In bright sunlight, using a large aperture can be impossible without an ND filter. A neutral density filter is also needed when you want to photograph, for example, flowing water in bright weather and with a really long exposure time.
The multi-coated and low-profile Irix Edge ND filter is designed specifically for the Irix 15mm f/2.4 lens.
Compatible:
Irix Blackstone 15mm f/2.4
Irix Firefly 15mm f/2.4