OpticalGlass:16LayerspremiummulticoatedopticalglassWaterproof,Scratchproof,Dustproof,Oilproof*Frame Function: SPLASH-PROOF, as they have a rotating ring in General ND filters, should not be used underwater.*What's is included: ND8/PL*Installation: Efficient SCREW-ON system for easily attaching/detaching*Made to be used with DJI Osmo Action Camera