The Lee Foundation Kit is the basic element of the Lee filter holder System. This kit contains all the necessary components (including a small screwdriver) to construct a versatile holder that when assembled in its standard form, accepts three filters - 100mm (4") wide x 2mm thick. It also holds 4x6" (100 x 150mm, 2mm thick) filters. The holder can be made to accommodate up to four 2mm thick filters by using the separately-available Lee Filters 3/4" Side-Guide Screws and an additional set of Side Guides for 2mm Thick Filters.
Lee makes a variety of standard and wide angle adapter rings in screw-in and bayonet sizes as well as accessory compendium shades. When mounted, this holder will rotate on the adapter ring for positioning a polariser or a graduated filter. Optional "side-guides" and guide mounting screws in shorter/longer lengths are available for use with 1mm and 4mm thick filters.