The Canon 0 Dioptric Adjustment Eyepiece Lens is a rectangular eyecup designed specifically for Canon digital SLR cameras. It is compatible with various Canon camera models such as 5D Mark II, 6D, and Kiss X50. Made by Canon in Japan, this unit weighs 10g and is a genuine Canon accessory, ensuring a quality fit and function for your camera. With no modifications required, this eyepiece lens provides a comfortable viewing experience for photographers using Canon EOS cameras.