Create your own custom resistance tubing lengths Used by many top level health clubs, hospitals, and fitness professionals Great for special applications; simply use scissors to cut your own desired length 25ft length; see infographic for approximated thickness This product may contain dry rubber or natural latex Workoutz 25 feet bulk resistance tubing is used by exercise researchers, medical institutions, and professional sports teams around the world. This is a superior quality product that will last a very long time. NOTICE: This product may contain dry rubber or natural latex. Yellow (4 - 5 lb max resistance), Green (7 - 8 lb max resistance), Red (9 - 10 lb max resistance), Blue (12 lb max resistance), Black (16 lb max resistance). All dimensions/specs approximated.