100 cotton. Poly/cotton blends are available by request. Names can be added to the back of the shirts for an additional 3.00. The color for the letters and designs can be changed along with the font. Not all letter fonts are vinyl cutter friendly, however i will try to get the closest font to the one requested. Names can be added to the back on tee for an additional 2.00. The shirt can be altered, made into a long sleeve, t shirt or rash guard. Please contact me with any inquiries. The vinyl is very durable and can withhold a multitude of washings. Please contact me directly for any large orders. Orders are typically shipped out within a week. This is just a precaution just in case my shop runs out of any materials. If you would like your shirt to be 'bedazzled', let me know ahead of time. I normally use rabbitskin, bella, gilden, hanes, and champion. If there is a particular brand that you would like, please let me know.