Boatneck, loose fit, stretchy fabric t-shirt. Should be hung to dry.
In picture, sizes are from left to right: Small, Large, Large, Medium. (XL is also available in some patterns) 
4 Designs Available: Paddle and Roll With the Heel and Toe, Release Relax Ready, Finish Your Shuffles, Hear the Rhythm(sold out)
 
You can instructional videos for the t-shirt lessons by clicking the following links:
https://www.youtube.com/watch?v=xFIBkqziBM4
https://www.youtube.com/watch?v=IY0QAOMj9OU