The bite valves and bladders of our packs are made of a TPU based compound. If you're wondering what is TPU made of, it is a thermoplastic elastomer that doesn't contain rubber.
Most rubber allergies are generally latex based. Latex is a naturally derived rubber which is known to cause skin irritation. Some of the agents that often cause allergic reactions are thiuram, carbamate, and mercaptobenzothiazole or proteins in latex.
TPU is rubber like in durability, flexibility and smooth, but is a synthetic thermoplastic elastomer, not a rubber based material. It's important to note the difference in tpu rubber vs silicone materials when considering allergies.
As always if you have an allergy we suggest researching further as you could have a TPU or synthetic compounds in TPU allergy.
Cheers!
Josh
Josh Sprague is the designer and CEO at Orange Mud. Designing packs and other gear is at the heart of his passions and Orange Mud as a brand. Making packs that are light, fast, functional, and always important, durable....is a major focus in his designs.