These straws are food-grade 18/8 stainless steel metal- a staple for any sustainable kitchen. Easy to clean, dishwasher safe, and rust proof. Best if used with tumblers, bottles, and cups in the following sizes: 20 oz, 18 oz, 12 oz, and 10 oz. Measurements: Length - 8.5” (215 mm); Width - 0.23” (6mm). Tip* Before washing in dishwasher, run an agave all natural bristle brush through it to remove buildup.