Tritan water bottles are a type of plastic that is free of BPA and any bisphenol, which makes them safer than other materials as they are completely safe to be in direct contact with food and drink, as well as not retaining odours and flavours. It has the advantage of being a very resistant and lightweight recyclable plastic, and can be washed in the dishwasher, stored in the freezer or put in the microwave without deterioration.
RPET, on the other hand, is recycled PET (plastic) made from waste material. It is often used for bottles and packaging, and the main advantage it has over other materials is that it generates fewer CO2 emissions than other materials.