I make Oxygen T-Shirt – Any more of that lip and I'll show you our deforestation techniques. Our I make Oxygen T-Shirt is under the Funny T-Shirts section of our store. Being one of our crowd pleasing designs, this Funny T-Shirt features a smarmy tree and it's smarmy opinion and on its front that says I make oxygen; what do you do? As one of our cool and comfortable tees it makes a great gift for someone who likes environmental jokes. We used a 100% cotton premium blank tee for this shirt. Our I make Oxygen T-Shirt is incredibly comfortable and it is made to last. Our Funny T-Shirts can be found in a color and size of your choosing. If you have any questions or suggestions regarding our I make Oxygen T-Shirt or any of our other Humorous T-Shirts let us know the name of the product and details of your question in an e-mail.