What is it???

[truetone36]

I received a strange item today. this thing came from a radio transmitter shack and I know it's a piece of transmitting equipment, but I don't know exactly what it does. Since I don't have a digicam I'll describe it in as much detail as I can.
It's a metal cabinet approx. 3 ft. tall by 18 in. wide by 18 in. deep. It contains 4 hollow aluminum cylinders which have coaxial cables connected to them. They are connected to each other in pairs. there are 2 coax cables running out of the top of the cabinet, one on the left and one on the right.
I'm no expert on transmitting gear, does anyone know what this is? Thanks in advance for any info.