That is my overview and demo of the Freewell ND and Polarized Filters for the DJI Spark. You should buy these filters right here:
https://freewellgear.com/69-dji-spark-filters-and-accessories

CHECK OUT THE AMAZON FREEWELL STORE: https://www.amazon.com/s?marketplaceID=ATVPDKIKX0DER&me=A2OGOWCR9BZX7P&service provider=A2OGOWCR9BZX7P&redirect=true