OBS_VALUE: The H-1B visa category is considered closest to contractual services suppliers. The quota is 65 000 per year.Depending on how contractual services suppliers is defined, and the circumstances of the service provided within the United States, other visa categories not subject to quota may be applicable. For example, an individual engaging in business activities other than the performance of skilled or unskilled labor may be classifiable as a B-1 (business) visitor.  Individuals may also be classifiable under B-1 when coming to the United States to install, service, or repair commercial or industrial equipment or machinery purchased from a company outside the United States or to train U.S. workers to perform such services, where the provision of such services or training is pursuant to a contract of sale.