US work visas requires the prospective employer to first file a petition with U.S. Citizenship and Immigration Services (USCIS). Offer Letter Requirements.Access our Job Search Tool Kit for more resources to help you apply for jobs at the County of Santa Clara. Make sure of the following. A) That the position mentioned in the LC was 'Product Engineer'. Use this letter to convey information to a new employee about whom they will report to, job title, starting date and time, rate of pay and classification. The IRC can help you to petition to bring your family members to the US, apply for citizenship, green cards, work authorization, travel documents, and more. Apply to Immigration Paralegal, Assistant, Legal Clerk and more! Use this sample letter to detail a job position to a temporary employee, stating the period of time for which he or she has been hired. To apply for public benefits - (408) 758-3800.