W.W. Grainger, Inc., together with its subsidiaries, distributes maintenance, repair, and operating products and services primarily in North America, Japan, the United Kingdom, and internationally. The company operates through two segments, High-Touch Solutions N.A. and Endless Assortment. The company provides safety, security, material handling and storage equipment, pumps and plumbing equipment, cleaning and maintenance, and metalworking and hand tools. It also offers technical support and inventory management services. The company serves smaller businesses to large corporations, government entities, and other institutions, as well as commercial, healthcare, and manufacturing industries through sales and service representatives, and electronic and ecommerce channels. W.W. Grainger, Inc. was founded in 1927 and is headquartered in Lake Forest, Illinois.

Fastenal Company, together with its subsidiaries, engages in the wholesale distribution of industrial and construction supplies in the United States, Canada, Mexico, North America, and internationally. It offers fasteners, and related industrial and construction supplies under the Fastenal name. The company's fastener products include threaded fasteners, bolts, nuts, screws, studs, and related washers that are used in manufactured products and construction projects, as well as in the maintenance and repair of machines. It also offers miscellaneous supplies and hardware, including pins, machinery keys, concrete anchors, metal framing systems, wire ropes, strut products, rivets, and related accessories. The company serves the manufacturing market comprising original equipment manufacturers; maintenance, repair, and operations customers; non-residential construction market; farmers, truckers, railroads, mining companies, schools, and retail trades; and oil exploration, production, and refinement companies, as well as federal, state, and local governmental entities. Fastenal Company was founded in 1967 and is headquartered in Winona, Minnesota.

WESCO International, Inc. provides business-to-business distribution, logistics services, and supply chain solutions in the United States, Canada, and internationally. It operates through three segments: Electrical & Electronic Solutions (EES), Communications & Security Solutions (CSS), and Utility and Broadband Solutions (UBS). The EES segment supplies products and supply chain solutions, including electrical equipment and supplies, automation and connected devices, security, lighting, wire and cable, and safety, as well as maintenance, repair, and operating (MRO) products. This segment also offers contractor solutions, direct and indirect manufacturing supply chain optimization programs, lighting and renewables advisory services, and digital and automation solutions. The CSS segment operates in the network infrastructure and security markets. This segment sells products directly to end-users or through various channels, including data communications contractors, security, network, professional audio/visual, and systems integrators. It also provides safety and energy management solutions. The UBS segment offers products and services to investor-owned utilities; public power companies; and service and wireless providers, broadband operators, and contractors. This segment's products include wire and cables, transformers, transmission and distribution hardware, switches, protective devices, connectors, conduits, pole line hardware, racks, cabinets, safety and MRO products, and point-to-point wireless devices. This segment also offers various service solutions, including fiber project management, high and medium voltage project design and support, pre-wired meters and capacitor banks, meter testing and metering infrastructure installation, personal protective equipment dielectric testing, and tool repair, as well as emergency response, storage yard, materials, and logistics management. The company was founded in 1922 and is headquartered in Pittsburgh, Pennsylvania.

MKS Instruments, Inc. provides foundational technology solutions to semiconductor manufacturing, electronics and packaging, and specialty industrial applications in the United States, Germany, China, South Korea, and internationally. It operates through Vacuum Solutions Division (VSD), Photonics Solutions Division (PSD), and Material Solutions Division (MSD) segments. The VSD segment provides foundational technology solutions, including pressure measurement and control, flow measurement and control, gas and vapor delivery, gas composition analysis, electronic control technology, reactive gas generation and delivery, power generation and delivery, and vacuum technology. The PSD segment offers range of solutions, which include lasers, beam measurement and profiling, precision motion control, vibration isolation systems, photonics instruments, temperature sensing, opto-mechanical components, optical elements, systems for flexible PCB laser processing, and laser-based systems, as well as high density interconnect PCB and package manufacturing. The MSD segment develops, process, and manufactures technologies comprising advanced surface modification, electroless and electrolytic plating, and surface finishing for chemistry, equipment, software, and services markets, as well as high-technology applications. In addition, the company sells its products and services through direct sales, network of independent distributors, and sales representatives, as well as websites, including product catalogs. The company was incorporated in 1961 and is headquartered in Andover, Massachusetts.

DXP Enterprises, Inc., together with its subsidiaries, engages in distributing maintenance, repair, and operating (MRO) products, equipment, and services in the United States and Canada. It operates through three segments: Service Centers (SC), Supply Chain Services (SCS), and Innovative Pumping Solutions (IPS). The SC segment offers MRO products, equipment, and integrated services, including technical expertise and logistics services. It offers a range of MRO products in the rotating equipment, bearing, power transmission, hose, fluid power, metal working, fastener, industrial supply, safety products, and safety services categories. This segment serves customers in the oil and gas, food and beverage, petrochemical, transportation, other general industrial, mining, construction, chemical, municipal, agriculture, and pulp and paper industries. The SCS segment manages procurement and inventory vinventory optimization and management, storeroom management, transaction consolidation and control, vendor oversight and procurement cost optimization, productivity improvement, and customized reporting services. Its programs include SmartAgreement, a procurement solution for various MRO categories; SmartBuy, an on-site or centralized MRO procurement solution; SmartSource, an on-site procurement and storeroom management solution; SmartStore, an e-Catalog solution; SmartVend, an industrial dispensing solution; and SmartServ, an integrated service pump solution. The IPS segment fabricates and assembles custom-made pump packages; remanufactures pumps; and manufactures branded private label pumps. DXP Enterprises, Inc. was founded in 1908 and is based in Houston, Texas.

MRC Global Inc., through its subsidiaries, distributes pipes, valves, fittings, and other infrastructure products and services in the United States, Canada, and internationally. It offers ball, butterfly, gate, globe, check, diaphragm, needle, and plug valves; other products, such as lined corrosion resistant piping systems, control valves, valve automation, and top work components; and valve modification services, including valve control extensions, welding, hydrotesting, painting, coating, x-raying, and actuation assembly. The company also provides carbon steel fittings and flanges comprising carbon weld fittings, flanges, and piping components; stainless steel, alloy and corrosion resistant pipes, tubing, fittings, and flanges; and carbon line pipes. In addition, it offers natural gas distribution products, including risers, meters, polyethylene pipes and fittings, and various other components and industrial supplies; oilfield and industrial supplies and completion equipment, such as high density polyethylene pipes, fittings, and rods; and specialized production equipment comprising tanks and separators. Further, the company provides various services under the ValidTorque and FastTrack names. Its products are used in the construction, maintenance, repair, and overhaul of equipment used in extreme operating conditions, including high pressure, high/low temperature, and high corrosive and abrasive environments. The company was formerly known as McJunkin Red Man Holding Corporation and changed its name to MRC Global Inc. in January 2012. MRC Global Inc. was founded in 1921 and is headquartered in Houston, Texas.

Global Industrial Company operates as an industrial distributor of various industrial and maintenance, repair, and operation (MRO) products in North America. It offers storage and shelving, safety and security, carts and trucks, HVAC and fans, furniture and decor, material handling, janitorial and facility maintenance, workbenches and shop desks, tools and instruments, plumbing and pumps, office and school supplies, packaging and shipping, lighting and electrical, foodservice and retail, medical and laboratory, motors and power transmission, building supplies, machining, fasteners and hardware, vehicle maintenance, and raw materials. The company offers industrial and MRO products under the Global, GlobalIndustrial.com, Nexel, Paramount, Interion, and Absocold trademarks. It serves businesses; state, local, and private educational organizations; and government entities through relationship marketers, e-commerce sites, signature campaigns, and catalogs. The company was formerly known as Systemax Inc. Global Industrial Company was founded in 1949 and is headquartered in Port Washington, New York.

The L.S. Starrett Company, together with its subsidiaries, manufactures and sells industrial, professional, and consumer measuring and cutting tools, and related products in North America, Brazil, and China. The company's products include precision tools, electronic gauges, gage blocks, optical vision and laser measuring equipment, custom engineered granite solutions, tape measures, levels, chalk products, squares, band saw blades, hole saws, hacksaw blades, jig saw blades, and reciprocating saw blades, as well as M1 lubricant and precision ground flat stock products. It also provides measuring tools, such as micrometers, vernier calipers, height distributors, depth gages, electronic gages, dial indicators, steel rules, combination squares, and custom and non-contact gaging such as vision, optical, and measurement systems. In addition, the company offers hand tools for measuring, marking, and layout that include tapes, levels, chalk lines, and other products for building trades, and construction and retail trades. It primarily distributes its precision hand tools, and saw and construction products through distributors or resellers. The company serves metalworking, wood, food, semi-conductor production, aerospace, medical, oil and gas, machinery, government, equipment, and automotive markets; marine and farm equipment shops, and DIY enthusiasts; and tradesmen, which comprise builders, carpenters, plumbers, and electricians. The L.S. Starrett Company was founded in 1880 and is headquartered in Athol, Massachusetts.