A very high quality filter 3 x 3" gelatin filter holder, this fits all lenses which accept 52mm threaded filters, though with lenses with focal lengths shorter than 24mm it is not recommended due to the possibility of vignetting.There's nothing fussy here, no little secondary metal frames to shoehorn in and out of the device; merely leave your filter in its originally-supplied paper casing and use tweezers or, quite carefully, your fingers placed only upon the filter's corner to take it from its case to the confines within this filter holder.
When using a polarizer filter in combination with gelatin filters, it is necessary that the polarizer be in front of the gelatin away from the film/image sensor.