ADTRAN Total Access® 3050 is designed to meet this demand by providing the ADSL/VDSL and POTS signal splitting/combining function. It is configured to integrate with the Total Access 3000 DSLAM using 28 Octal splitters or cut-through modules per chassis and is ANSI T1.413 compliant. The shelf is a solid metal design with a latched, hinged, metal front cover for easy access. A filtered airflow is maintained from the front of the chassis. The Total Access 3050 utilizes a four-pole splitter design and no active components are on the standard splitter modules. No direct current (DC) blocking capacitor is required. ADTRAN designs products that maximize functionality for its carrier customers. In that regard, the Total Access 3050 accommodates other service cards such as SHDSL, IMA, IDSL, DS1 FR, CES, and DSX-1. These can be utilized by installing a cut-through module instead of a splitter module in the corresponding shelf. The rear of the shelf has twenty 50-pin and eight 64-pin amp connectors, one DB-25 connector for Metallic Test Access (MTA) and one RS-485 wire-wrap bus for daisy chaining splitter shelves. There is a standard power connector for -48V, -48V return and chassis ground. The system will also support MTA. With the addition of the metallic test control module and modules with MTA, the shelf will interface with metallic test heads and provide access to the loops. There are MTA modules for both ADSL and cut-through applications.