What information should an internship offer letter include?

The offer letter must be on company letterhead (or a company branded email) and will include:

• Company name and address
  -Job title (preferably is called an XXX intern)
  -Start and end dates
  -Number of hours per week
  -Estimated total hours to be completed on the internship
  -Location where the student will be working
  -Supervisor name, title and contact information
  -Signed (electronic signature is accepted)