I have designed this pattern so that you can make it any size you need. Using an I hook, and worsted weight yarn, the smallest size will fit a 24 inch chest. Use Baby yarn and a smaller hook, if you would like to make it even smaller. Add more rounds, and rows to make it larger. The instructions include how to use the measurements of your favorite fitting tank top to custom design a crochet version.
Pictures of many of the steps.

Written in American crochet terms.