These hiking boots are designed with ReBOTL™ fabric lining containing at least 50% recycled PET plastic and a TimberDry™ membrane that helps keep your feet dry. The "Does it Fit?" sockliner helps you know when it's time for a bigger pair, while the OrthoLite® footbed helps cushion feet. By purchasing this product, you are supporting Leather Working Group certified tanneries https://www.leatherworkinggroup.com/ The ReBOTL™ material used in Timberland® apparel contains at least 40% recycled PET (recycled polyethylene terephthalate, the stuff plastic bottles are made of). The ReBOTL™ material used in Timberland® footwear and accessories contains at least 50% recycled PET. (Excepting trace materials) OrthoLite® comfort foam insoles are lightweight, provide moisture transport, antimicrobial function, and long-term cushioning. The ultra-breathable material won't break down or lose cushioning over time, keeping your footwear comfortable and supportive. A waterproof membrane made with at least 50% recycled plastic. Our waterproof footwear incorporates a variety of advanced waterproofing materials, treatments and processes. We start with waterproof leathers that are sealed as part of the tanning process; we then either seam-seal the footwear or use an internal waterproof breathable membrane to help feet stay dry. Tongues and zippers treated with durable water resistant coatings utilize integrated gussets, to further deter water entry.