DI Optical is headquartered in South Korea. For many years, they worked as an OEM manufacturer for other renowned companies in the industry of optics – Steiner, Bushnell, and others. Recently, they started selling some of their devices, predominantly red dot sights, under their own brand. DI Optical manufactures all kinds of red dot sights; they are one of the few out there who make red dot sights for machine guns. Reliability and robustness are the main assets of their devices – it is no coincidence that DI Optical red dot sights are one of the main choices of NATO.