Middle Atlantic 3SP Flanged Wrinkle Blank - WSB3

Middle Atlantic WSB3 3U Flanged Steel Rack Blank Panel

Overview

The Middle Atlantic WSB3 is a 3U flanged blank panel designed to fill unused rack spaces in 19-inch equipment enclosures. At just 0.52 inches deep and rated to carry 50 lbs by UL, the WSB3 does two jobs at once: closes off open rack slots to maintain proper airflow and adds a load-bearing surface if you need to support lightweight shelf items or cable management accessories. It ships as a single unit — one panel, ready to mount.

For integrators building out rack accessories and enclosure kits, this is the kind of detail item that gets overlooked on the BOM and then holds up a clean rack finish on install day. Stock a few of these alongside your active gear so you're not improvising with cardboard or leaving gaps that disrupt front-to-back airflow in climate-sensitive server rooms or IDF closets.

Key Features

• 3U height (5.25 in): Fills exactly three rack units of open space — useful when you have an odd gap between a network video recorder and a patch panel that a 1U or 2U blank won't cover cleanly.
• Flanged construction (steel): The flanged style means the panel seats against the rack rail face and stays flush without relying solely on the screw holes for alignment — easier to install solo and less likely to bow under incidental contact.
• 50 lb UL-rated load capacity: The UL load rating of 50 lbs (22.7 kg) means you can rest lightweight accessories — a small cable management bar, a label printer, a thin shelf — on top without voiding a listed installation. Most unmarked blank panels carry no load rating at all.
• Black wrinkle powder coat finish: The textured black wrinkle powder coat matches Middle Atlantic rack enclosures and most standard Middle Atlantic rack furniture. It also hides fingerprints and minor handling marks better than a smooth gloss finish — practical in a working IDF cabinet that gets opened regularly.
• 19-inch standard width: Fits any EIA-standard 19-inch rack rail — open-frame, wall-mount, or enclosed cabinets. No adapter rails needed.
• Two mounting points: Ships with two mounting points — one per rail side. Standard #10-32 or M6 fastener compatibility depending on your rack's tapped holes.
• 0.52-inch depth: At just over half an inch deep, the WSB3 won't interfere with cable runs or rear-mounted equipment in shallow-depth wall-mount enclosures where every inch of depth counts.

Integration and Compatibility

The WSB3 is compatible with any EIA/ECA-310 compliant 19-inch rack, including open-frame two-post racks, four-post enclosed cabinets, and wall-mount enclosures. It works alongside the full Middle Atlantic rack panel line for mixing 1U, 2U, and 3U blank fills to cover non-standard gaps. The panel width of 19 inches and standard two-point mounting pattern means it drops into virtually any commercial rack without modification.

For security integrators building NVR or access control enclosures, pairing blank panels with a structured rack enclosure plan from the start prevents the ad hoc fixes that create airflow problems and messy front panels later. The 50 lb load rating also makes the WSB3 a candidate for supporting a small PoE injector or compact device that doesn't warrant a full shelf.

What's in the Box

• 1x Middle Atlantic WSB3 3U Flanged Blank Panel

Frequently Asked Questions

Q: What rack unit size is the WSB3?

A: The WSB3 is a 3U panel, measuring 5.25 inches in height — it fills exactly three rack units of open space in a standard 19-inch rack.

Q: Will the WSB3 fit my existing rack enclosure?

A: Yes, provided your rack is a standard EIA 19-inch rail configuration. The WSB3 measures 19 inches wide and uses a two-point mounting pattern compatible with virtually all commercial open-frame and enclosed 19-inch racks.

Q: Can I rest equipment on top of the WSB3?

A: The WSB3 carries a UL-rated load capacity of 50 lbs (22.7 kg), so lightweight accessories and small devices can be placed on it within that rated limit. Verify your rack enclosure's own load ratings as the limiting factor for heavier loads.

Q: How deep is the WSB3?

A: The WSB3 is 0.52 inches (1.3 cm) deep — shallow enough for use in wall-mount enclosures and other tight-depth installations without conflicting with rear cable runs or mounted equipment.

Q: Does the WSB3 come with mounting hardware?

A: The WSB3 ships as a single panel with two mounting points. Rack screws are not included in the documented package contents — use #10-32 or M6 fasteners matching your rack's tapped holes.

Q: What finish does the WSB3 have?

A: The WSB3 features a black wrinkle powder coat finish on steel construction, which matches standard Middle Atlantic rack furniture and resists fingerprints better than smooth-finish panels.

Karl Wilson

The WSB3 is one of those items I always add to a rack build BOM after getting burned by an open gap on a finished install. That 50 lb UL load rating is the detail that separates it from generic import blanks — on a commercial job with a listed enclosure, having a rated panel matters for the inspection record, not just aesthetics.

Technical Highlights:

• UL Load Capacity (50 lbs): Most no-name blank panels carry zero load rating. At 50 lbs, the WSB3 can support a compact PoE injector or small managed switch temporarily staged during a phased installation without pulling the enclosure's listed rating.
• Flanged steel construction: The flanged edge seats flush against the rack rail face independent of screw tension, which means the panel stays aligned even before you tighten the fasteners — useful when you're racking solo or working in a tight wall-mount enclosure.
• 0.52-inch depth: In shallow wall-mount cabinets (8–12 inch depth), every fraction of an inch matters for rear cable clearance. At 0.52 inches, the WSB3 won't press against a bundle of Cat6 runs the way a deeper stamped panel would.

Deployment Considerations:

• Mounting hardware is not included — verify whether your rack uses #10-32 or M6 tapped holes before the install day so you're not hunting for fasteners on-site. The WSB3 ships as panel-only per the documented package contents.
• The wrinkle powder coat finish matches Middle Atlantic enclosures well, but if you're mixing with smooth-finish racks from other manufacturers, the texture difference will be visible. Not a functional issue, but worth noting on client-facing installations where aesthetics matter.

The WSB3 is the right call for any commercial rack build — security head-end, access control panel enclosure, or IDF closet — where the enclosure is a listed assembly and you need a load-rated, finish-matched blank to close out the job cleanly.