Park's Professional Pedal Wrench features an angled, oversize head for maximum leverage. It has 15mm and 9/16-inch wrenches to fit all pedals, and a long, round, vinyl-coated handle that won’t dig into your hand the way flat wrenches do. There's even a hole in the end for hanging the wrench on your toolboard.
Hint: the right pedal is turned clockwise to tighten, counter-clockwise to loosen. But, the left pedal is "reverse" thread. Turn it clockwise to loosen and counter-clockwise to tighten.