Grainger and McMaster Carr are two major industrial suppliers that specialize in next-day delivery of maintenance, repair, and operating (MRO) supplies. Both companies maintain extensive product catalogs with over 500,000 products and focus on servicing commercial and industrial customers. Grainger utilizes a multichannel business model including sales representatives, e-commerce, inventory management solutions, and an extensive branch network to provide customers with flexibility in ordering. McMaster Carr also focuses on next-day delivery and maintaining a wide selection of products from a single source to meet customer needs.