I test every set of filter rings I send out, but something might have changed recently at DJI because I had a few people that told me their rings don't fit. For those people I custom printed a new size, usually 0.5% larger, and sent it to them for free.
To compensate for slight manufacturing variences both at DJI and at DitzCo, I have redesigned the clip to adjust automatically. I am in the beta testing process now and I sent out some samples today. If your filter clip doesn't fit please let me know and I will send you a new one for free.
This is especially important for the Phantom 3 Standard as it doesn't have the screw-on factory UV filter. You need a press-on filter kit for the Standard and this kit works great for that. When you are ready to upgrade your Phantom you will still be able to use my ND filter kit with it even if you upgrade to the Phantom 4.
Filter Material Update, for months now I have been shipping filters made with Lee filter material. I have been getting much better quality and they are thicker which makes them easier to use and they are also less susceptible to static electricity. The optical quality is great too.
For those that are interested, I use Autodesk Fusion 360 for my design work. I create both the CAD files and the renderings with it. For this update I created new geometry to create one spring. I was then able to create a circular pattern so I could change to 2, 3 or 4 springs if I wanted with much less work.
After I get feedback from user testing, I will update my store with the new design.