Nalgene 32 oz Narrow Mouth Loop Top - SustainExperience sustainability with Nalgene. As industry experts, we are pleased to introduce a cutting edge resin utilizing advanced recycling methods to convert landfill bound plastic into top quality, BPA BPS free bottles. Our innovative Nalgene Sustain collection is comprised of 50% certified recycled materials, effectively reducing the reliance on fossil fuels and minimizing greenhouse gas emissions.