B-Line SB5777138TG Eaton series open frame racks, Steel, Telco gray powder coat, 12-24 panel mounting holes, 66 mounting spaces, Top channel style, Seismic Zone 4, network bay open duct rack, Grade 33, ASTM A570

66 mounting spaces on the rails, which is 66 rack units of usable equipment height at 138 inches overall. That is well above the common 45U floor rack, so it suits a network bay where you are stacking a lot of patch panels and switches in one footprint.

The rails carry 12-24 panel mounting holes, the standard telco threading. Your patch panels and gear need 12-24 screws; 10-32 hardware will not thread in, and cage nuts are not used because these are tapped holes rather than square punchings.

Yes, the SB5777138TG is built as a Seismic Zone 4 network bay open duct rack, which is why it uses the top channel style construction to tie into overhead bracing. It is also UL Listed.

Width is 23 inches and the listed length/depth figure is 138 inches; height is also 138 inches. Plan aisle clearance off the 23 inch width when you are laying out a row of bays.

An open frame bay like the SB5777138TG gives you access from all four sides and open air movement, which is what you want for patch panels, cross connects and switch aggregation in a secured room. If the space is shared or public, or you need locked doors and controlled airflow front to back for servers, an enclosed cabinet is the better call. This frame has no doors or side panels.

ASTM A570 grade 33 steel with a Telco gray powder coat. That is the standard gray used across central office and network bay equipment, so it matches existing telco lineups and ladder rack hardware in the same finish.