I designed this diffuser for my Olight Arkfeld (non-pro), and it works perfectly. The fit is so precise that it even creates a slight suction when removing it. I printed it using white PLA, as I found that transparent TPU didn’t diffuse the light enough. I couldn’t try white TPU since I didn’t have any at the time, but I believe it would work well. You can use the same slicer settings—just make sure to switch to the appropriate filament.