Key Module

Expansion Module for GXV3350, GRP2615, GRP2624, 20 dual-colored extension keys and 2 arrow keys for page switching (allowing each GBX20 to support up to 40 contacts/extensions.) Connect up to 4 GBX20

Expansion Module for GXV3350, GRP2615, GRP2624, 20 dual-colored extension keys and 2 arrow keys for page switching (allowing each GBX20 to support up to 40 contacts/extensions.) Connect up to 4 GBX20 modules to compatible Grandstream phones for a total of 160 contacts/extensions.