RIFTON PACER LARGE GAIT TRAINER K503 , REHAB WALKER , 200 LBS CAPACITY. The Pacer gait trainer is a Class 1 medical device. It is designed to help a user learn to walk. For a user lacking active use of his or her trunk and leg muscles, the Pacer provides the necessary support during gait training and requires little or no weight-bearing. This is a large Pacer and it is recommended for users with elbow height of 31″– 46″ (79–117 cm). The maximum working load for the large Pacer is 200 lbs (91 kgs).