These pictures are to help identify whether you have a Boston Model 17 electric pencil sharpener. You can click on any image for an enlarged view.For starters, note that the brand name on the front cover (this pulls out and is the shaving's tray too...) bears the brand name Hunt Boston.
The length of the unit from the edge of the faceplate / tray is about 7 and 15/16 inches. The width is about 3 and 6/16 inches.
Centered on the back of the unit is a case screw.
On the bottom of the unit should be (unless it fell off or was removed) a label with the model number, serial# and other information.
Note there are two case mounting screws (missing in this photo) in the center also to hold the sharpener case closed and suction cup feet to hold the sharpener still if on a flat surface.