The KGA080-A-MT Geltech Molded Glass Aspheric Lens is a very economic choice for collimating or focusing light at high magnification. It is made from Corning C0550 glass, which features low dispersion (Vd=50.40). Typical applications include fiber coupling, laser diodes, medical lasers, optical data storage, and barcode scanners. This 6.325 mm diameter lens has an effective focal length of 3.89 mm and a 0.55 NA. It has a Visible anti-reflective coating for 350-700 nm and is mounted in a durable stainless steel housing with a threaded exterior.