The used DJI Osmo ND4 Neutral Density Filter offers an effective solution for exposure control for the DJI Osmo Handheld 3-Axis Gimbal w/ X3 4K Camera. Key features include:

Filter Factor. This ND4 filter will cut two stops of light from your exposure.

Common Uses. Neutral Density filters are commonly used for slowing shutter speeds to capture movement (such as waterfalls, clouds, and cars), as well as allowing the use of wider apertures in bright conditions to decrease depth-of-field.