Line M Up snaps onto your golf ball to allow you to easily and accurate add alignment and identification marks. There are many different marking options that allow for a variety of uses. Use your marks to align your shot or tell if your putt is rolling straight. Line M Up also works great to add uni...

Stuart Walker, a world champion celebrated for his books and columns on racing in Sailing World magazine, here takes his readers step by step through the elements that determine racing factors: wind direction, velocity, temperature, stability, current strength, and direction. These racing factors, D...