Purchase invoice: It should be requested at the same time as the order and will be sent by email. In the absence of the billing data, the tax receipt that will not be possible to cancel will be issued. The SBM24 keys module increases the number of line keys for calls and functional keys on an Avaya 9600 series phone suitable for IP Avaya 9608, 9608G, 9611g, 9641g and 9641gs IP Deskphone phones A separate power supply is not necessary. However, the use of more than one buttons module changes the phone power class in class 3 IP Office 6.0 to 8.1 - Compatible with Avaya IP phones 9630, 9630g, 9640, 9640g, 9650 and 9650c. It can add up to 3 SBM24 modules by phone; Up to 42 SBM24 per system. IP Office 9.0 or higher - Compatible with IP Avaya phones 9608, 9608G, 9611g, 9630, 9630g, 9640, 9640g,.