The tres petit corona (often shortened to TPC) is the smallest size in the corona family. The Cuban factory size, called the Perla, is 102 mm (4 inches) long with a 40 ring gauge, and Habanos gives its smoking time as about 20 minutes. Non-Cuban cigars sold under this name are usually about 4 to 4½ inches long, with a ring gauge from the high 30s to the low 40s.
It is a straight parejo with a high proportion of wrapper to filler, so you taste the wrapper and the blend quickly. That makes it a practical short smoke and an easy way to try a line without spending an hour on it.
The next size up is the petit corona, followed by the classic corona. Guide: corona and petit corona.