What does 1200-50 belt sander mean?

1200-50 belt sander refers to a belt sander with a length of 1200mm and a width of 50mm.

Belt grinder is a kind of equipment specially used for grinding and polishing metal hardware. 1200-50 belt sander means that its length is 1200mm and its width is 50mm. The abrasive belt machine grinds and polishes the metal surface through the rotation and friction of the abrasive belt to remove surface defects, oxides and corrosion.