Power Mod™ skinny mains are up to 45% narrower than the standard main devices because they only allow for one feed direction. The existing standard 200-1200A WB mains are wider because they allow for combination feed, hence the "C" suffix in the part number.

Combination feed models allow the installer to feed cables through either the top or bottom of the unit. The skinny mains only allow the installer to pull cable into the unit from one predetermined direction. Be sure to use a unit with a "B" suffix for bottom feed and "T" suffix for top feed. If you are uncertain of which feed direction will be needed on the job, please avoid using the skinny mains and use combination feed units in these instances.

Check out the Flyer from the DLC: www.siemens.com/download?BTLV_49808