Rare, extra-fine dental floss. This is a set of 10 rolls, each 50m long, and does not include a case. Because it's extra-fine, it can be used even by those with very narrow spaces between their teeth, and is highly recommended. 【Shipping and Packaging】 The product will be wrapped in a waterproof bag and shipped directly in an envelope. Please note that the packaging will be simple, without bubble wrap. Shipping will be via Yu-Packet Post (anonymous delivery) using Yu-Yu Mercari.