APC’s NetShelter SX 1,200-mm-deep enclosure has an additional pair of cable channels at the rear of the enclosure for organizing more power and data cables and room to mount power distribution. The channels enable the mounting of as many as four vertical rack power distribution units (PDUs) on one side of the enclosure. The NetShelter SX is available in three different sizes—42U/600 mm, 48U/600 mm and 42U/750 mm.