RM-3 allows mounting of one or two small profile type BTI products horizontally in one rack space. The blue rack shelf is flanged for strength and is equipped with eight 6-32 stand-offs. The front panel is pre-drilled with six 1/4″ holes that may be used for ventilation, or to mount user-provided switches, push buttons, LEDs etc. Mounting hardware is included. 4.6 inches deep.