The Natural Fitness (Plant-a-Tree) Adjustable Resistance Tubes Kit w/DVD has 3 Tube Levels and 2 Adjustable Handles. This Kit includes: 3 Levels of Natural Rubber Resistance Tubes (Harvested from the sustainable rubber tree.) This makes it superior to synthetic rubber in performance, resilience and to Mother Earth. The levels are: Light, Medium and Heavy for smooth, safe exercise and toning. Build up to your best level safely. The 2 Adjustable Handles are made from Recycled Plastic, with Comfortable Foam Padding. You can easily change Resistance with the Adjustable Handles and their Special Locking Mechanism. The included Exercise Instruction Chart provides a full body workout. Included is A FREE DVD by Renowned Fitness Expert, ANDREA METCALF. She will have you in shape in no time at all! Great For Travel, Business or Pleasure. Work-out on your time schedule. You can play and still look great! Don't forget to bring the DVD for instruction, if still needed. Resistance training is a form of strength training in which each effort is performed against a specific opposing force generated by the resistance created in stretching the resistance tube. It is called "isotonic" exercise when the body part is moving against the force, or stretching the tube. Holding that resistance against the force, the exercise becomes "isometric" exercise. Resistance exercise is used to develop the strength and size of skeletal muscles. Properly performed, resistance training can provide significant functional benefits and improvement in overall health and well-being. The goal of resistance training is to gradually and progressively overload the musculoskeletal system so it gets stronger. Research shows that regular resistance training will strengthen and tone muscles and it INCREASES BONE MASS! Resistance training is a real positive for those suffering from a lack of bone mass. About Natural Fitness: If it's made by Natural Fitness, an innovative, eco-friendly yoga and fitness company, it means that you are receiving a quality product. Natural Fitness uses a solar powered web host which captures 100% of its electricity from photovoltaic panels located on its roof. They also use all recycled packaging,and solar power for their offices and manufacturing plant. Natural Fitness also Plants-a-Tree in the rain forest for each of their products we sell! Planting a tree helps offset the environmental impact from manufacturing and transportation of your purchase. The trees are planted in areas of the rain forest that have degraded soils from slash and burn farming, clear-cutting and over use. Trees help stabilize erosion while rebuilding the soil and protecting nearby streams and rivers. These trees absorb CO2 and other greenhouse gasses. Trees also release vital oxygen for decades while they provide important sustainable resources to the local communities such as food, fiber, fuel and building materials.