The tiptel KD40-33 is an expansion module for the tiptel 3340. It is connected to the PC port of the IP phone. A maximum of six modules can be used with one IP phone. The tiptel KD40-33 has 40 BLF function keys on two levels. It is possible to switch quickly between the levels via two separate keys. Each key has a bicoulored LED. The programming of the expansion module is carried out with the IP phone.