Metal Project Box. Nice RF tight box measures about 3" x 2", the mounting foot print is about 4" x 2". About 1-3/4" tall. Each box has a set of nice N Female connectors, one on each end. Any inside parts (components inside box will differ from box to box) can be removed. Nice thick wall box. Barrier strip on top and feed thru points. These can be used for RF preamps, switches, amps, etc the list is limitless. Perfect for HAM radio and experimenter use. Heavy.