Specify MRK series when you need an enclosure built to perform like a workhorse. Its rugged, space-saving design and high seismic load rating make it a favorite of installing contractors, particularly on larger-scale multi-bay jobs. The MRK series also offers seismic certification and open or removable sides.ite of installing contractors, particularly on larger-scale multi-bay jobs. The MRK series also offers seismic certification and open or removable sides.Fully welded construction for strengthRacks gang together when fully loadedMultiple lacing points and slotted rail brackets for cable management flexibilityStandard front and rear adjustable 10-32 threaded rackrail with numbered spaces