Disposable sanitary bags. Keep them in a portable pouch for use when you're out and about. They also have a zip closure to prevent odors from leaking. One pack contains 16 bags, and there are 4 packs in a set. Additional sets are available for 200 yen each. It's a much better deal than buying from a 100-yen shop, as you get a larger quantity. They will be shipped discreetly in a waterproof bag via Yu-Yu, Mercari's anonymous delivery service. Thank you.