Rotating Polarizer Filter for Matte boxes with no rotating stage. Built into a single-stage self-contained unit, the Rota Pola Rota-Tray 4 x 5.65" with Circular Polarizer from Revar Cine is a compact, easily rotatable polarizing solution for most matte boxes that accept 4 x 5.65" filters. Rather than requiring a full 4 x 5.65" glass filter, the Rota-Tray uses an included 138mm diameter filter which sits inside the rotating tray. If the polarizer needs to be adjusted, simply rotate one of the geared wheels, which extend from the top of the tray on either side. The included filter is a 138mm mid-efficiency circular polarizer manufactured from Schott B270 glass. It features 38% transmission (1.5 stops of light loss) and broadband antireflective coating for reducing unwanted flares. The tray itself has a lightweight and rigid aluminum construction.