ADC RIG-I-Flex Model 142 is recommended for stage and TV studio cyclorama installations where it is necessary that the operator walk the curtain to its opened and closed positions. The track can be shipped with pre-made 90 degree curves or can also be custom curved on-the-job. The minimum recommended radius is  2 feet (layout dependent). No cord or pulleys are supplied with "walk-along" tracks. Model 4252 Master Carriers are used with the systems. 

ADC RIG-I-Flex Model 142-R is identical to Model 142 except that No. 4237 Single Carriers and No. 4253 Master Carriers are used.