A fitness device for mounting on a door is useful for performing resistance exercises. The fitness device includes an upper member including a door anchor for securing the upper member to the door and a pulley support bracket having a pivot pin. The fitness device also includes a lower member including a door anchor for securing the lower member to the door and a pulley support bracket having a pivot pin. An elastic cord extends generally between the upper and lower members and is associated with two pulley members. The pulley members are configured to be removably received on the pivot pins. The pulley members include bores having keyways and the pivot pins include nubs configured to be received in the keyways.