ADC RIG-I-Flex Model 142R is recommended for lighter duty stage and TV studio cyclorama installations where it is necessary that the operator walk the curtain to its opened and closed positions. The track is curved on-the-job and can be bent to a minimum radius of 2’ (layout dependent). No cord or pulleys are supplied with "walk-along" tracks. Model No. 4237 Single Carriers and No. 4253 Master Carriers are used with these system.