Aluminum shingle

Claim 1

AN ALUMINUM SHINGLE OF RECTANGULAR SHAPE, SAID SHINGLE COMPRISING A SHEET OF METAL WITH ONE SIDE EDGE REVERSELY BENT TO OVERLIE THE UPPER FACE OF SAID SHEET AND THE OPPOSITE SIDE EDGE REVERSELY BENT TO UNDERLIE THE LOWER FACE OF SAID SHEET TO PROVIDE MEANS FOR INTERLOCKING LATERALLY ADJACENT SHINGLES, THE LOWER EDGE OF SAID SHEET BEING REVERSELY BENT TO UNDERLIE THE LOWER FACE OF SAID SHEET TO PROVIDE MEANS FOR INTERLOCKING SAID SHINGLE WITH THE ADJACENT LOWER SHINGLE, THE UPPER EDGE OF SAID SHEET BEING REVERSELY BENT TO OVERLIE THE UPPER FACE OF SAID SHEET TO PROVIDE MEANS FOR INTERLOCKING SAID SHINGLE WITH THE ADJACENT UPPER SHINGLE AND AN INTEGRAL FASTENING TAB AT THE UPPER CORNER OF SAID SHEET ADJACENT SAID ONE SIDE EDGE, SAID TAB COMPRISING AN EXTENSION OF SAID REVERSELY BENT UPPER EDGE PROJECTING OUTWARDLY OF THE ADJACENT REVERSELY BENT SIDE EDGE, SAID EXTENSION OVERLYING THE UPPER END OF THE ADJACENT REVERSELY BENT SIDE EDGE TO CLOSE THE UPPER END OF THE CHANNEL FORMED THEREBY TO PREVENT UPWARD FLOW OF MOISTURE TO THE UNDERSIDE OF SAID SHINGLE, AND A PORTION OF SAID EXTENSION BEING BENT UPWARDLY IN THE OPPOSITE DIRECTION OF, AND ALONG A BEND WHICH IS PARALLEL TO, SAID REVERSELY BENT UPPER EDGE TO PROJECT UP BEYOND SAID REVERSELY BENT UPPER EDGE.