What Is a Social Security Number (SSN)? A SSN is a nine-digit identifying number is in the format xxx-xx-xxxx. Any individual who is a U.S. Citizen, a permanent resident, or a temporary alien resident who is authorized to work in the United States, must have a SSN.
The most common cause of a flat tire is puncturing of the tire by a sharp object, such as a nail, letting air escape. Depending on the size of the puncture, the tire may deflate slowly or rapidly.
1 Rough edges from tube liners or worn internal surfaces in tires. 2  Tube liners have been reported to cause punctures, and this author has experienced a slow puncture at the free end of a liner in a two month old tube. 3  When a tire's cladding is frayed or holed, it can rub on the tube and cause damage.