Manufactured by the brand Weider, the PRO 4100 is a home gym system designed for home use alone. The Weider PRO 4100 is meant for use on leveled surfaces, for anyone above the age of 12 years and weighing below 300 pounds. As the machine's amount of resistance is increased, it pushes the muscles to the maximum endurance limit, hence, providing a complete work-out for the muscles. However, the resistance of the machine should be increased progressively, either by changing the amount of weight used or by changing the set of activities performed on this home gym. The dimensions of the machine measure 77 inches in height, 81 inches in width, and 59 inches in length. The Weider PRO 4100 is equipped with a military press for the shoulders and the upper arms. Butterfly arms and press arms have been installed for the arms, the chest, and the shoulders. The system has a backrest to prevent injuries and slipped discs while exercising. For exercising the muscles of the legs, the system is enhanced with a leg lever which works on the hamstrings, a leg press plate for the quadriceps, and a foot plate for absorbing shocks. The upper pulley and the lower pulley connect to the weight and, thus, the user can adjust the weights and intensity according to his or her capacity. The Lat bar is installed for the Latissimus Dorsi. Weight loss is another program designed by Weider, which was established in 1942. Joe Weider, who founded this brand, is a world-famous body builder. Machines, equipment, and other health care products for body building, fitness, health, and wellness are some products designed by him. The Weider brand has been in existence for the past 70 years, and is listed on the NYSE (1997).