Exhibit 21
W.W. GRAINGER, INC.
Subsidiaries as of January 31, 2011
Acklands - Grainger Inc. (Canada)
- Solus Sécurité Inc. (Canada)
Dayton Electric Manufacturing Co. (Illinois)
GHC Specialty Brands, LLC (Wisconsin)
Grainger Caribe, Inc. (Illinois)
Grainger Colombia Holding Company, Inc. (Delaware)
- Grainger Colombia S.A.S. (Colombia) (80% owned)
Grainger International, Inc. (Illinois)
- Grainger Global Holdings, Inc. (Delaware)
- Grainger China LLC (China)
- Grainger Global Trading (Shanghai) Company Limited (China)
- Grainger India Private Limited (India)
- Grainger Panama Services S. de R.L. (Panama)
- WWGH LLC (Delaware)
- Grainger Panama S.A. (Panama)
- Grainger Services International Inc. (Illinois)
- MRO Korea Co., Ltd. (Korea) (49% owned)
- MonotaRO Co., Ltd. (Japan) (47.8% owned)*
- ProQuest Brands, Inc. (Illinois)
- WWG de Mexico, S.A. de C.V. (Mexico)
- Grainger, S.A. de C.V. (Mexico)
- MRO Soluciones, S.A. de C.V. (Mexico)
- WWG Servicios, S.A. de C.V. (Mexico)
Grainger Japan Holdings, Inc. (Delaware)
- Grainger Japan, Inc. (Delaware)
- MonotaRO Co., Ltd. (Japan) (5% owned)*
Grainger Latin America Holding Company, Inc. (Delaware)
- Grainger Trinidad, Inc. (Delaware)
Grainger Service Holding Company, Inc. (Delaware)
Grainger Services Network, Inc. (Delaware)
- Grainger Safety Services, Inc. (Delaware)
Grainger Worldwide Holdings, Inc. (Delaware)
- India Pacific Brands (Mauritius)
- Grainger Industrial Supply India Private Limited (India)
Imperial Supplies Holdings, Inc. (Delaware)
- Imperial Supplies LLC (Delaware)
- Imperial Logistics LLC (Wisconsin)
Zoro Tools, Inc. (Delaware)
*W.W. Grainger, Inc. owns a total of 52.8% of MonotaRO Co., Ltd. (Japan)