Mower blades themselves aren't threaded, but rather the fastener that holds the blade in place can be either right or left-threaded. Right-hand threaded fasteners tighten clockwise and loosen ...
Is it OK to shake somebody's left hand? How about passing the salt with your southpaw? We've got the tea on the times you shouldn't use your left hand, and we're about to spill it—with the proper hand ...