This is a set of four K&F Concept NANO-X series ND filters for the DJI OSMO ACTION. I purchased them new on Amazon last year. The package says they are for the OSMO ACTION 4, but they can also be used with the OSMO ACTION 5 PRO. I actually used them a few times with the ACTION 5 PRO, but haven't used them since, so I'm putting them up for sale. - Brand: K&F Concept - Model Name: NANO-X Series Filters - Filter Type: ND Filter - Number of Filters: 4-piece set Thank you.