Metal food grater, 3 sided, hinged on both sides of the middle side, hand held type with curved wires for holding upright on two sides. One of the sides is for regular grating, at a medium size, one is a double slice side for larger flakes and the third is a rind grating side for smaller and finer grating. Probably used for cheese, vegetables, etc.
Grater, F895.2002. The Museum of Transport and Technology (MOTAT).