This book goes into detail explaining how these modern, essential tools of anglers work and how to use them to gain an understanding of where you are and what the watery world beneath you contains. If you are trying to determine what the best unit for your type of fishing is then this book will help you to unravel the mystique surrounding these electronic marvels. Those wishing to use depth sounders will learn the features that are available and how they affect the display, plus how to set-up the sound for your type of fishing learn how to use this equipment to consistently and accurately return to those areas where you have angling success.