SmallRig Filter Frame Kit (4 x 5.65") 3649, accessories for Star-Trail and Revo-Arcane series matte box, is designed to balance exposure under complex light environment by allowing installing multiple slide-in filters. It comes standard with two filter frames (4 x 5.65") and one stackable Clamp-On Back. Among them, the 4 x 5.65" filter frames come with aluminum alloy frame and anti-off safety lock that allows quick release and secure locking of filters as well as prevents fingerprints; the stackable Clamp-On Back, made of aluminum alloy and installed via magnets, has quick-release safety lock that works well with matte box, VND Filter Kit 3651 and Filter Frame (4 x 4") 3648. The kit also adopts a variety of quick-release designs to give the greatest quick release convenience to users of Star-Trail and Revo-Arcane series matte box.