Get a top quality product for a top quality workout. The Obsidian Surge 500 Water Rower will keep your workouts engaging and challenging. Studies have indicated rowing can work up to 85% of the body’s muscular system without the joint impact of other conventional cardio exercises. This in turn results in higher calorie expenditature in a shorter period of time. Elevate your workout and be more efficient with the Obsidian Surge 500 Water Rower.