17 oz Collapsible Water Bottle is made of PE with Carabiner, reusable sports water bottle is environmentally friendly & saves you money wasted on bottled drinks. The bottle can be collapsed flat when empty for easy storage and travel. Ergonomic design stands upright when full, fitting most auto cup holders. The Carabiner expands portability and holds the bottle in the folded position when empty. Freezer friendly. BPA free.