The ARC075 Anti-Rollback Cam is a simple device which can be retro-fitted to the ZipSpeed-S model (RP075). During normal use, the cam trails, allowing the trolley to roll forwards, unhindered. However, as soon as the trolley begins to roll backwards, the cam is activated, bringing the trolley to an immediate halt. This anti-rollback function captures the progress of the trolley, which means that even when the trolley doesn’t reach the end of the Zipline, it cannot roll backward and hence rescue distance (and therefore, rescue time) is significantly reduced.