Can cheap ND filters be good? The K&F Concept SN25T1 filter kit says yes
Amazon.com : K&F Concept 55mm Variable ND Filter ND2-ND32 Camera Lens Filter (1-5 Stops) No X Cross HD Neutral Density Filter with 28 Multi-Layer Coatings Waterproof (Nano-X Series) : Electronics
Amazon.com : K&F Concept 58mm Variable ND2-ND400 ND Lens Filter (1-9 Stops) for Camera Lens, Adjustable Neutral Density Filter with Microfiber Cleaning Cloth (B-Series) : Electronics
K&F Concept 67mm Magnetic Variable ND Filter ND2-ND32 (1-5 Stops) + Magnetic Filter Adapter Ring Filter Kit, No X Cross Adjustable Neutral Density Filter with 28 Multi-Layer Coatings Waterproof
K&F Concept ND2 to ND400 ND Lens Filter Slim blue film Fader Variable Adjustable Neutral Density 49mm 52mm 58mm 62mm 67mm 77mm - AliExpress
K&F Concept CPL/ND Filter Kit for DJI Mini 3 Pro SKU.1956 B&H
Amazon.com : K&F Concept 67mm Variable ND Filter HD ND2-ND400 (9 Stops) with Putter 28 Multi-Layer Coated Janpanese Optical Glass Adjustable Neutral Density Filter for Camera Lens (Nano-X II) : Electronics
B Series,ND2-ND400 - K&F CONCEPT
Amazon.com : K&F Concept 58mm Variable ND2-ND400 ND Lens Filter (1-9 Stops) for Camera Lens, Adjustable Neutral Density Filter with Microfiber Cleaning Cloth (B-Series) : Electronics
Amazon.com : K&F Concept 82mm Variable ND Filter ND2-ND32 Camera Lens Filter (1-5 Stops) No X Cross HD Neutral Density Filter with 28 Multi-Layer Coatings Waterproof (Nano-X Series) : Electronics