The Cokin Z121M has a progressive graduation from the middle to the top of the filter, with the same colour as the 121 filter, but with a lower tone.
The Cokin Z Filters
Aimed at the professional and enthusiast photographer, the Z-PRO series total over 80 different filters including coloured, centre spots, pastel/ diffusers to graduated and neutral density filters.
The Z-PRO filters are available in two different sizes. The plain filters, i.e. coloured, centre spots and pastel/diffusers measure 100x100mm in size and the graduated filters 100x150mm. All Z-PRO filters are manufactured from high quality CR39 organic glass and fit the Cokin Z-PRO holder system.
Compatible with all 100mm filter holders, including Lee