Device for preventing sewer backflow

FIG. 1 is a perspective front, top and right side view of a device for preventing sewer backflow;

FIG. 2 is a perspective front, bottom and right side view of the device for preventing sewer backflow of FIG. 1 ;

FIG. 3 is a top plan view of the device for preventing sewer backflow of FIG. 1 ;

FIG. 4 is a bottom plan view of the device for preventing sewer backflow of FIG. 1 ;

FIG. 5 is a right side elevational view of the device for preventing sewer backflow of FIG. 1 ;

FIG. 6 is a front elevational view of the device for preventing sewer backflow of FIG. 1 ;

FIG. 7 is a left side elevational view of the device for preventing sewer backflow of FIG. 1 ; and,

FIG. 8 is a rear elevational view of the device for preventing sewer backflow of FIG. 1 .

The broken lines shown in the drawings are for the purpose of illustrating portions of the device for preventing sewer backflow and form no part of the claimed design.