It's service

The E-3 classification is available exclusively to qualifying nationals of Australia seeking to come to the United States to perform services in a specialty occupation. Like the H-1B classification, the position must involve the theoretical and practical application of highly specialized knowledge and require, at minimum, a bachelor’s degree in a specific specialty or its equivalent.
 
Our E-3 Specialty Occupation Expert Opinion provides an independent, industry-specific analysis of the proffered position. The expert examines the actual job duties, their specialized nature, complexity, level of responsibility, and occupational context to determine whether the position requires the application of specialized knowledge and a minimum of a bachelor’s degree in the field identified by the employer. The opinion provides professional evidence supporting the specialty-occupation nature of the position beyond the position title alone.
 
We also provide combined Specialty Occupation, Academic, and Work Experience Evaluation services for E-3 cases. These integrated services include an expert evaluation of the position together with an assessment of the beneficiary’s academic credentials and/or qualifying professional experience for purposes of establishing the required U.S. degree equivalency. Pricing for the combined services is the same as our corresponding H-1B combined services.