The Royal Double Station Overhead Twister is a whirlwind way to get in shape. It works the muscles of the upper limb, such as the biceps, triceps, pectoralis major and minor, the deltoids, and the teres major. It also works and strengthens the abdominal muscles. Besides working and strengthening these muscles, this piece of exercise equipment also corrects posture. Up to two people can use to it get in shape at a time. Its frame is made from a galvanized steel tube, and it comes with stainless steel hardware. It is manufactured to be free of sharp edges. The Royal Double Station Overhead Twister is part of the royal fitness series and made out of commercial grade material that has a tough powder coated finish to ensure maximum durability. This finish will ensure that it lasts for many years of outdoor use from people who are 13 years old and older.