When you open the incoming package, you will find that the packaging is very high quality. The brand is very careful in presenting their products and the materials are of high quality. The filter holder and adapter ring are metal and the filter holder has a spongy area whose function is to seal with the filter without letting light through. Once the filter holder is attached, it is easy to move. crtsal 100x100 quality is very good, with highly polished edges. The filter holder has two slots for square filters, but the advantage is that the ring screwed on the lens can be screwed with another round filter, for example a polarizing filter. I think the picture is very good. As with the brand's round filter, the sharpness is not lost, the color cast did not catch my eye, anything that can be edited during development is appreciated. The ND1000 filter included in the kit enables long exposures in strong light. The sample photos are photos taken on a cloudy afternoon with and without a filter. Those with filters were made with an exposure time of 20 seconds.