2-Pack (Two NOSSK GYM Trainer systems)! VERSATILITY: Though NOT meant to be used on the door, can be used on ALMOST ANY SUPPORT. IDEALLY used in a GYM (Professional Fitness Center or Home Gym) on a bar or hooks on a wall – attaches in seconds. The soft loop on the strap will not mar the bar. The height of the Grips are easily adjusted with the 2 Cam Buckles. Trainer is up to 8ft long. And, yes this trainer can also be used OUTDOORS on e.g. a tree branch or even on a vertical post – so, take your GYM to the next level and get ready for your next Boot Camp with the NOSSK GYM Pro Trainer!