253 is four inches referring to fig4 a perspective view of an assembled rack mount with an attached flat panel display is shown the support brackets 410 420 are positioned opposed to each other with one support bracket 410 on the right and the other support bracket 420 on the left hanging rod 430 is suspended between the support brackets 410 420 hanging rod 430 is inserted in the slotted key holes 418 428 in the support brackets as discussed above in relation to fig2 the hanging bracket 450 hangs from the hanging rod 43 by the attachment wings 454 the hanging rod 430 is inserted through the holes 458 in the attachment wings 454 flat panel display 400 is attached to hanging bracket 450 the upper flat portion 453 of the hanging bracket 450 lies along the upper side of the flat panel display 400 the hanging bracket 450 and the flat panel display 400 slide horizontally along the axis of the hanging rod 430 the support brackets 410 420 define the limits of the extent to which the hanging bracket 450 and the flat panel display 400 can slide in either direction along the axis of the hanging rod 430 the hanging bracket 450 and the flat panel display also rotate around the axis of the hanging rod 430 as discussed in relation to fig2 in a preferred embodiment of the invention the length of the upper flat portion 453 is such as to allow the flat panel display to hang.