The signamax voice grade MT-Series keystone jacks have been designed to support voice-transmission network applications and low speed data transmission applications. These connectors are slim in profile for high density applications and have the ability to mount either color coded icons for service identification or dust covers to protect unused jacks from dust and other contaminants. Special design features allow these jacks to be terminated with a standard 110 single port tool or with the signamax four pair tool. The connector contact design provides enhanced plug-to-jack connection integrity, protects against damage caused by insertion of 4- or 6-position plugs and is rated for a minimum of 750 plug insertions providing for the highest level of system reliability.