Here is a simple tool designed to help you stretch your calves. The Exercise Slant Board Calf Stretcher has 4 adjustable angles: 8°, 18°, 28°, 38°. It is 18″ wide and 13.5″ long. The device has a non-slip surface to provide you with a safe stretch.
The unit holds weighs up to 350lbs. It helps you stretch your hamstrings, calf muscles, and more. Costs under $90 at this time.