The rack is the steel structure that holds and services everything else: a 48U-class OCP/MGX frame, a sheet-metal chassis for every tray, telescopic rails so trays slide out, and casters and feet so the integrated rack can roll in and stand level. Supermicro’s GB300 NVL72 enclosure measures 600 × 1,068 × 2,236 mm (W × D × H), and Rittal rates its MGX rack for dynamic loads up to 1,400 kg.
The structure: a 48U-class open-rack frame with its panels, a tray chassis on slide rails, and the casters and leveling feet the integrated rack stands on.
The frame carries the weight and sets where every tray, busbar and manifold sits. Each tray’s chassis rides on slide rails, and the casters and feet move and level the whole rack.
Illustrative rack frame and chassis example. Designs differ by manufacturer; the model is not a bill of materials.
What to look for: The posts and cross members of the frame, the tray chassis with its guides, the nested rail sections and ball bearings, and the wheels and feet at the base.
Why do rails and tray chassis matter in an AI rack?
Liquid-cooled compute trays are dense and heavy, must dock blind into power, coolant and copper-spine connectors at the rear, and must slide out for service without draining the loop. Chenbro designs its GB200 NVL72 tray chassis for blind-mate liquid cooling, and King Slide lists an AI-server rail among its developments. Neither names the racks its parts go into.
Who makes the casters and leveling feet?
We have not verified a supplier. Rack makers ship frames with casters and feet fitted, and neither they nor the system builders in our sources name the component makers. The part is shown as a declared gap rather than filled with a general industrial stock.
King Slide makes server rail kits and lists an AI-server rail among its 2024 developments; Chenbro makes MGX compute-tray chassis for GB200 NVL72 and Vera Rubin NVL72. Vertiv supplied AI infrastructure racks for a DGX GB300 deployment and Dell sells its own ORv3 IR7000 rack, while the MGX-rack makers Rittal and Cheval are private.
Open each company below for its source and limitations. Sector membership does not establish a confirmed supply contract.
Inside the assembly
Rack frame & panels
A reinforced steel frame of posts, cross members and panels sized for wide trays, a rear busbar and manifolds. The compute and switch trays alone weigh roughly 675 kg in NVL72-class designs.
Stock-link scope: Schneider Electric launched a rack system for NVIDIA GB200 NVL72 on the MGX architecture (June 2025), and Delta and Lite-On show racks for NVIDIA MGX. Vertiv says the three-rack configuration it deployed for the Naval Postgraduate School’s NVIDIA DGX GB300 included ‘AI infrastructure racks’ with power and liquid cooling (July 23, 2026), without saying whether they house the GB300 itself. Dell sells its own ORv3 21-inch IR7000 rack with its GB300 NVL72 systems; the fabricator is not disclosed. Legrand sells OCP racks with an ORv3 busbar, nVent lists server racks (AI-rack use not established) and AVC lists server cabinets. The MGX-rack makers Rittal (MGX Architecture Rack for GB200/GB300 NVL72, Oct 14, 2025) and Cheval (ORv3 MGX rack for GB200 NVL72) are private. Supermicro, Lenovo and Chenbro ship complete racks without naming the frame maker.
Also in this part (not publicly listed):Rittal Not publicly listed, Cheval Electronic Enclosure Not publicly listed, Chatsworth Products (CPI) Not publicly listed
Tray chassis
The sheet-metal enclosure of each compute or switch tray, with its lid, bezel, guides and mounting points for boards, cold plates and drives.
Stock-link scope: Chenbro sells an NVIDIA MGX 1U compute-tray chassis for GB200 NVL72 (two superchips, blind-mate liquid cooling) and a 1U tray for Vera Rubin NVL72, with no named customer. Foxconn Industrial Internet reports server chassis within its precision mechanical parts (double-digit growth in 2025), with no AI share given, and AVC makes server chassis and cabinets beside its thermal products. Wiwynn’s annual report lists rails and chassis among purchased inputs, so integrators generally source them from suppliers. Builders’ own tray designs (QCT’s D75B-1U, Supermicro’s ARS-121GL-NB3) sit under Builders, not here.
Telescopic ball-bearing rails that let a heavy tray slide out for service and keep it aligned as it docks into the rear connectors.
Stock-link scope: King Slide’s 2024 Sustainability Report lists an ‘Advanced AI Server Rail’ among its 2024 developments and a strategy of deeper penetration of cloud data centers (11.0 million rail sets made in 2024). Its customers and GB200/GB300 platform wins are press-reported (CommonWealth, May 2026), not disclosed. Other rail makers (the private Accuride, and Taiwan’s Nan Juen) could not be verified in our September 2026 review and are not listed. Fositek says it makes high-load rails for architectures such as GB300 (2025 annual report); AVC holds 16.87% of Fositek and consolidates it.
Heavy-duty wheels that let an integrated rack roll from the factory to its row, and feet that take its weight and level it once in place.
Stock-link scope: GAP: no listed or private caster or leveling-foot supplier is verified for NVL72-class racks. Rack makers ship frames with casters and feet fitted, and neither they nor the system builders in our sources name the component makers. Industrial caster makers are not mapped without AI-rack evidence.
No verified direct company match in the current universe.
Disclosed: AVC’s 2025 annual report describes cold plates, CDUs, manifold systems and fans for AI servers, and its Q2 2026 results put servers at 66% of revenue.
Disclosed: Dell’s 8-K gives AI-server orders, revenue and backlog; its blog and product pages describe the GB300 NVL72 systems, the IR7000 rack and the eRDHx.
Disclosed: Delta’s GTC 2026 release and data-center catalog describe power shelves, BBUs, cold plates and CDUs for NVIDIA platforms, including a GB300 NVL72 in-rack CDU; NVIDIA lists Delta among its 800 VDC partners.
Disclosed: Fositek’s 2025 annual report says its UQDs entered the GB200/GB300 supply chain and passed Rubin testing; its H1 2026 results put servers at 55.7% of revenue.
Positioning: Legrand’s AI data-center page lists its rack PDUs, ORv3 vertical busbar, OCP racks and rear-door heat exchangers; no named AI-rack customer.
Partner-disclosed: NVIDIA’s technical blog says the GB300 NVL72 power supply’s energy storage was co-designed with LITEON; Lite-On’s GTC 2026 release covers its 800 VDC power rack, shelves and CDUs.
Disclosed: nVent’s release says it worked with NVIDIA to define a GB200 NVL72 reference architecture using its CDUs, heat exchangers and manifolds, and quotes NVIDIA.
Disclosed: Vertiv’s product page names the PowerDirect 3000 shelf for GB200 and GB300, and its release describes a GB300 NVL72 reference architecture; NVIDIA lists Vertiv among 800 VDC partners.
Evidence groupings are not investment ratings. Companies may appear in multiple sectors.
Also in this sector (not publicly listed)
Rittal Not publicly listed
German enclosure and cooling maker (Friedhelm Loh Group) named by NVIDIA among Blackwell partners; its rack-level role is not verified in our sources.
Bangkok-based enclosure maker (Cheval Group) selling an Open Rack V3 NVIDIA MGX rack for GB200 NVL72 (600 × 1,068 × 2,236 mm, 1,600 kg load rating), also listed on the OCP marketplace. We found no exchange listing; its ownership is not documented in our sources.
