But to qualify for mailing at the First-Class Mail postcard price, it must be: 1  Rectangular. 2  At least 3-1/2 inches high x 5 inches long x 0.007 inch thick. 3  No more than 4-1/4 inches high x 6 inches long x 0.016 inches thick.
eligible - qualified for or allowed or worthy of being chosen; eligible to run for office; eligible for retirement benefits; an eligible bachelor. qualified - meeting the proper standards and requirements and training for an office or position or task; many qualified applicants for the job.
Eligibility Requirements. The eligibility requirements for joining the armed forces can differ between branches. Knowing the requirements can help you avoid wasting time and effort. An issue that may make you ineligible for one service may be acceptable for another service. This Section will help you wade through some of the basic eligibility questions and hopefully narrow down the service that best fits your situation.