Collapsible Trekking Water Bottle — 1L BPA-Free, Carabiner Loop

Regional Notes:
US/CAN: Standard baseline. Women's: add 1.5 to men's UK size.
UK: Common in UK, Australia, and most African markets (South Africa, Nigeria).
EU: Universal standard for luxury and designer footwear. Whole + half sizes.
CM / Asia (JP/CN/KR): Most precise system. Measure your foot length in millimetres and round to nearest 5mm.

If between sizes: Size up for wider feet, size down for narrow. Most performance shoes run true to size.