Product Name: Coral Filter / Color Filter / Aquarium Filter Available Apertures: Multiple apertures are available, including 30/37/40.5/43/46/49/52/55/58, 62/67/72/77/82/86/95mm Frame Material: Light Aluminum Metal Frame Frame Process: Anodized Matte Black + Laser Marking Frame Thickness: Approximately 4.3mm Lens Material: Optical Resin Lens (Not Abrasion - Resistant) Coating: Uncoated Main Function: Reducing Blue Light for Observing Corals and Photographing Aquariums Common Scenarios: Used in marine aquariums to reduce blue light for observing corals, photographing aquariums, and for fun photography, etc.