CWS Gran Chaco Program Gran Chaco T-Shirt Designs This is the design file for the front of the CWS Gran Chaco T-shirt. This is a .EPS file download used for the actual printing of a shirt. Download Chaco T-Shirt Front This is the design file for the back of the CWS Gran Chaco T-shirt. This is a .EPS file download used for the actual printing of a shirt. Download Chaco T-Shirt Back