This antenna has a two wire fly lead supplied for connection to a variety of water meters. The connection to the water meter is not supplied and this will vary according to the type of meter you are connecting to. Note: it can only work if the meter has a pulse output and you will need to obtain the correct interface cable from the water meter supplier to connect to these two wires. Once connected, this enables the AT301 to receive the water meter signal data and display the consumption and cost on the Control Panel in almost real time with a 10 minute delay. This short antenna is used if you wish to connect the AT301 to the water meter and the radio signal between the Control Panel and Control Unit is not affected by any shielding. If the signal is poor and the AT301 Control Unit is being shielded, then you will need to use the Part # ANT2-3N which extends the antenna by 3 metres so it can be placed in a spot where it will receive the radio signal more clearly.