This grater was made by the Lorraine Metal Manufacturing Co. The company started in 1868 and was out of business in 1953. Hard to say exactly how old but looks to be 1920s or 1930s.
It is 2 1/2" x 4 1/2" x 8 1/2" and clamps to a table. I liked the sea foam green paint on it and as it clamps to a table does not really take up any space. Would have been used for cheese or nuts.