B-Line Eaton series open racks, 200 lb, Steel, Telco gray powder coat, 12-24 panel mounting holes, 48 mounting spaces, Top channel style, Seismic Zon

The SB5878090TG is drilled with 12-24 panel mounting holes and gives 48 mounting spaces (48U) of usable rail. Standard 19-inch EIA panels and equipment with 12-24 screws mount directly; if your gear ships with 10-32 or M6 hardware you will need 12-24 screws and cage-free tapped rails are already threaded, so no cage nuts are involved.

Rated at 200 lb load capacity. That is the equipment load, separate from the rack's own 119.6 lb shipping weight. For heavy switch chassis or battery strings you want a higher-rated frame; for patch panels, fiber housings, and typical network gear across 48 spaces this rating is the number to size against.

Yes. The SB5878090TG is built as a Seismic Zone 4 network bay closed duct rack and is UL Listed. Seismic rating depends on the anchorage as installed, so the floor attachment and any top bracing to overhead structure have to be executed per the seismic detail on the drawing for the rating to carry through.

Plan on a 90 inch overall height and 23 inch width. The stated depth figure is also 90 in, so confirm your room layout against the physical unit before laying out aisles. At 90 inches tall it needs a ceiling with clearance for the rack plus any overhead cable runway or ladder tray landing on the top channel.

A closed duct bay uses enclosed vertical channels for cable, so jumpers and patch cords run inside the uprights instead of hanging on the outside of an open two-post relay rack. That keeps a telco or network room bay tidy and protects the cable. If you only need mounting rails and will add separate vertical managers, a basic open frame rack costs less structure; if the bay is going to carry high patch cord density, the closed duct version is the one specified.

It is a top channel style frame, which gives you the horizontal channel across the top of the bay that cable runway, ladder rack, and overhead bracing land on. That is how you tie multiple bays together into a lineup and how the seismic top bracing gets attached. Runway, waterfall, and bonding hardware are ordered separately.

48 mounting spaces equals 48U of usable mounting height on a 90 inch tall frame. In practice a two-post network bay of this size takes a full mix of 1U and 2U patch panels, fiber enclosures, and switches with room left for horizontal managers between them, as long as the total equipment weight stays inside the 200 lb rating.

11 gauge steel throughout, finished in Telco gray powder coat. That gauge is the heavy end for open frame bays and the powder coat is the standard central office gray, so it matches existing telco bays in a room where you are adding a frame rather than starting fresh.