High-hardness scratch-resistant glass material: The lens is made of high-aluminum glass with increased hardness, resistant to scratches from sand and dust during flight. The high-quality white glass base offers excellent light transmittance, ensuring color accuracy during high-speed dives. Metal frame: Constructed from CNC aluminum material, the frame is strong, lightweight, and resistant to deformation. Provides effective impact resistance and helps prevent the filter from loosening or falling off. ND filter: Reduces incoming light, prevents image overexposure, and maintains natural motion blur during high-speed flight. UV filter: Clear and colorless, provides physical protection against scratches from branches or gravel while maintaining original image quality. Multiple specifications: Includes UV, ND8, ND16, and ND32 filters to suit a variety of everyday shooting conditions. Name: Filter Kit Compatibility: Designed for O4 Air Unit Pro Filter types: UV, ND8, ND16, ND32 Product appearance and printed markings may vary slightly by batch; this does not affect functionality. Color: As shown Material: CNC aluminum + high-aluminum white glass Package Contents: 1 x Filter Kit (other items not included) Note: Lighting and display differences may cause slight variations in color. Measurement tolerance: +/- 1-3 cm.