This Aico EI168RC Radiolink base main powered cell back-up easy-fit.\r\nThis is the base unit for all the compatible EI160 and EI140 series.\r\nThis base receives and transmits radio signal, this means that the base is required for all alarms on the system.\r\nThis item is mains powered however it also has a rechargeable 10 year lithium cell back-up.\r\nThis allows for protection even when faced with a possible power cut.\r\nThe unit can connect to 12 items within the system through the use of 868.99 MHz.\r\nThe type of building will factor into how well they transmit between them all, so it is advised that 30m should be the maximum distance between any of the alarms in the system\r\n.\r\nThis Acio EI168RC Radiolink comes with a 1 year guarantee, as do all of our products.