The STB module provide a connection point between an exchange-side cable pair and a distribution pair. It incorporates a 5-point plug in module to provide continuity and a range of other options. Removal of the plug-in module does not disturb wire connections but makes contacts to them available for testing of both sides of the network.

It is especially recommended for:
1. Outdoor connections where the enviromental conditions are extremely agressive.
2. Terminations where user development characteristics require future flexibility in terms of the type of protection or filtering capabilities.