GKU D900 CPL Adapter - Stop Reflections

If you own a GKU D900 dashcam, you know the frustrating problem of dashboard reflections that ruin your recordings. This 3D-printed adapter solves it definitively by mounting a standard 30.5mm CPL (Circular Polarizing) photography filter directly on your dashcam lens.

The Key Advantage: The adapter features precision threading (Ø30.5mm, pitch 0.5mm) perfectly compatible with standard photography CPL filters. During printing, I used variable layer height to achieve perfectly functional and precise threading, allowing the CPL filter to screw on smoothly without play or excessive tension.

Print Specifications:

• Material: PETG (excellent heat resistance for vehicle use) or ASA (even better for UV resistance and durability)
• Printer: Bambu Lab Carbon X1C
• Key Technique: Variable layer height for precision threading
• Threading: Standard photography M30.5x0.5
• Simplicity: Quick print, no supports required

Compatibility:

• Dashcam: GKU D900
• Filters: Standard 30.5mm CPL (easily available online)

Benefits:
✅ Completely eliminates dashboard reflections
✅ Drastically improves daytime video quality
✅ Rotating CPL filter for optimal adjustment
✅ Quick and reversible installation
✅ Heat-resistant materials for vehicle interior

Note: CPL filter not included - purchase separately. I recommend any 30.5mm CPL photography filter (B+W, Hoya, FOTGA, etc.)

I bought it on Aliexpress because it also had locking screws:
https://it.aliexpress.com/item/33044795793.html