Abstract: A cutter, for cutting various surfaces having various curvatures, having a blade assembly and a housing. The blade assembly includes a first blade and a second blade, each having an inner edge and an outer edge, and a guide mounted between the first blade and second blade adjacent to the inner edges thereof. The first blade has a first cutting surface and the second blade has a second cutting surface which are each oriented toward the guide. The first cutting surface is convex toward the guide and the second cutting surface is concave toward the guide, wherein the user may cut concave or convex surfaces by selectively using one of the blades.