Xlent Expandable Floss treated with Activated Charcoal expands between teeth once contacting saliva to create maximum contact with teeth and gums to remove plaque.Xlent floss also contains Xylitol, a plant based wax, and a fresh mint flavor for refreshing breath and healthy gums. Our product is cruelty free and not tested on animals. Expandable floss is slightly thicker than traditional floss, and may not be suitable for those with very tight spaces between teeth.