The drawing on the "El Teatro Radio" shirt, officially known as the "Peyote Radio Theater" design, was created by Jeff Buckley himself. It is significant because it was the only piece of merchandise he designed and approved during his lifetime. 

The design features a stylized drawing, sometimes described as a skull or a figure, which some sources suggest he also used on tour posters and in his personal diaries. The design has become a significant symbol for fans and is one of the most recognizable, authorized pieces of his visual legacy.

Happy to answer questions. A great find for a collector.