I got the ND8/ND16/ND32/CPL kit. The filters are high quality and well made. The included plastic case is very functional, but a bit bulky. Considering the quality and the fact that this kit costs about half of what the Insta360 "official" ND filter kit costs, it is definitely a good value. They are quite large however, and while this doesn't necessarily affect funtionality, it's something to be aware of. You can see in the photos the diameter of the filters is almost twice that of the original lens guard. That being said, they fit and thread on very well. I like that the CPL has a white indicator on the edge so you can keep track of the angle you have it set to.Just be aware that using filters on an action camera comes with some extra challenges. CPL can get a little funky with the super wide angle action cam lenses - the effect can seem uneven or weird depending on your shooting conditions, it can be tricky to use. As far as using the ND filters - normally the goal is to achieve the 180 shutter rule, i.e. get your shutter speed locked to be twice your framerate, to achieve the best motion blur. However, when your using an action camera which leans heavily on electronic stabilization, this doesn't really work. For example, if you are shooting in 4K30 and use the correct ND filter to expose correctly with a manual shutter speed of 1/60, it's going to muck up the stabilization and your footage is going to be bad with ugly jitter if you are moving the camera. You really need to keep the shutter speed at 1/240 so the stabilization can work properly.That being said, these are really nice filters, I'm not 100% sure if there is a reason they need to be so large, maybe it's to help prevent light leakage or weird flares or to help with the effect being even across the lens. Either way, it's not really a problem in the end, and the quality of the filter is what really matters.