... are available:: Can choose many kinds of requesters: HY-2610A, HY-2610B, HY-2610C, HY-2610E 1-button requester can transmit 1 request ... can transmit 2 request messages (service and cancel), 3-button requester can transmit 3 request messages (service, bill and cancel). And ... coverage is needed, we have signal enhancers for the system. 3) Service progress is visible: with the service queue number ...