【Only For Mini Matte Box】SmallRig filter tray 3320 is an optional accessory which works with SmallRig mini matte box, lightweight and easy to store. It prevents plug-in filters from minor bumps. If the dimension of your filter is (4 x 5.65") please buy SmallRig filter tray 3319 | 【Fits 4 x 4" Filters】This filter tray bracket allows for quick installation of 4 x 4" plug-in filters of 4 mm in thickness. With this filter tray, you're no longer to worry about leaving scratches and fingerprints when you're replacing the filters, its bezels will help to solve your troubles | 【Quick Release】The filter tray holder 3320 can be quickly and smoothly mounted and removed to the matte box via a NATO clamp, and when you hear a "click" that means that the tray holder has been installed and fixed | 【Stackable Design】The filter frame is stackable, it supports multiple filters at the same time, therefore you can have a free filter combination according to your shooting needs | 【Note】This Filter tray is not compatible with 100 x 100 mm filters. And generally speaking, you can use two kinds of SmallRig filter tray(for 4 x 4" and 4 x 5.65") at the same time, but make sure to install the filter tray (4 x 4") at first, otherwise the vignetting will appear