Abstract: A metal shingle system which is resistant to leakage, even under severe weather conditions. The key attribute of the new system to the design of the side edge of the shingle such that water that seeps between adjacent shingles cannot be blown upward. Briefly, the top edge is overturned and the bottom edge is underturned such that they can be interconnected as is well known in the art. One side edge is folded to form a gutter area into which water that seeps between laterally adjacent shingles is collected and drained onto the lower row of shingles. The top of the gutter area is blocked by the overturned top edge, which extends into the gutter region. Also disclosed is an improved tool for cutting the shingles, such as is needed around obstructions and at the end of the roofline.