The 685FAP2500 is a Longpass Filter with a 25 mm diameter, sourced from Knight Optical. This filter is designed to transmit light at wavelengths above 685nm while blocking light at wavelengths below this point. The filter's cut-on wavelength is 685nm, and it has a cut-off wavelength of 2200nm.
The filter is made from UVFS MAL-1965, a type of acrylic material, and has a thickness of 1mm. It features a Thin Lens shape and is coated with KNI 685FAP on both the front and back surfaces. The filter's geometry includes a diameter of 25mm, making it suitable for a variety of optical applications.
According to the vendor's information, this item is currently in stock and available for purchase. For more details, you can visit the following link: https://www.knightoptical.com/stock/default/acrylic-colour-filter-25mmdia-685nm-long-pass.html