309 COM 45501 XMIT loadable single user £203.00
309 COM 45502 XMIT loadable site licence £3,505.00
309 COM 45503 XMIT loadable corporate licence £17,524.00
The XMIT function is included with some controllers (i.e. Momentum family) and must be purchased for other ones (i.e. Quantum family). What controller and what software package are you using?