Horizon Fitness CST3 Treadmill Horizon Fitness Updated September 15, 2021 20:19 For the 2005 Horizon Fitness CST3 Owner's Guide, please click here. For the 2005 Horizon Fitness CST3 Exploded Diagram, please click here. Was this article helpful? Yes No 0 out of 0 found this helpful Have more questions? Submit a request Related articles How Do I Contact Customer Tech Support? Comments 0 comments Please sign in to leave a comment.