The Grad kit 4 contains a full set of the most popular warming color / temperature correction graduated filter - Coral - in densities 1, 2, and 3. The Coral soft edge color graduated effects filter is a pale pink color. Coral Filters can be considered as both Color Correction and Color Effects Filters and are used to warm cool lighting situations such as overcast days. Soft edge grads have a smooth transition from clear to ND. Hard edge grads have a more defined hard lined transition and are usually used for longer focal lengths. Different graduated color filters can be used in combination together or with solid color or neutral density filters to give interesting bespoke effects. This 100mm filter kit is usable with Formatt Hitech 100mm holder systems or any 100mm holder. The filters in this kit are 100mm Wide but 125mm long to enable easy movement up and down in the holder. The kit is also available in 85mm, 150mm and 165mm sizes. Formatt Hitech filters are made from the highest quality 1.5mm optical resin.