cnReach Hop offset is used for allowing multiple Master (AP) clusters in the same areas to same the same ISM frequeny band in frequency hopping. To get this to work, all radios sharing the same band needs to have the same Hop pattern, with MMS sync enabled. Each cluster will have an unique hop offset. For example, hop offset = 0 means starting with channel 0 and hop on. hop offset = 5 means starting with channel 5 and hop on. So you can see if the clusters are operating on different hop offset, they will be always using different channels of the band so they will not cause interference.