Features: brand new and high quality Fully reduce viewing and enhance contrast: With digital cameras, the IR Pass filter works well for solar infrared imaging, reducing viewing and improving contrast when used for lunar and planetary imaging. The IR Pass 685nm filter is made from high-end glass and is multi-coated using an ion-assisted deposition technique to ensure scratch resistance and central wavelength stability. The filter is made of light, strong metal and is CNC machined, sandblasted, black anodized and then laser sculpted. The result is an ultra-thin filter with a net aperture of 26mm. Filter darkens the twilight for sky background to capture moon and planetary mages at dawn or dusk. In addition to astronomical applications, ir-Pass filters can also be used for near-infrared nature photography to reveal surprising differences in plants, skies and clouds (requiring the use of a camera sensitive to infrared above 670nm, such as as a modified DSLR or webcam). The filter is located in a high-quality filter frame. Specifications: Material: B260 Size: 3.18cm/1.25in Substrate Thickness: 1.1mm Optical Aperture: 26mm Wavelength Range: 350-1100nm Cut-off Wavelength: 670nm Light blocking: OD2@400-660nm for Peak transmission: 670nm @ for T = 50% 673-1100nm @ T> 95% Surface quality: 60/40 Surface parallelism: 1/4 Parallelism: 30 inches Material: Aviation aluminum 6061T6 Thread: M28.5 x 0.6 Single thread: Yes Note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1 X Telescope Filter