A simple, battery-free slider that sticks to any pill, vitamin, or supplement bottle and shows at a glance whether today's dose is done. The tactile click marks "taken" or "not taken" to help prevent missed or double doses, and the durable adhesive re-sticks through a dozen-plus refills. Slim and travel-ready, it's a genuinely useful gift for anyone managing daily meds — or a caregiver who helps.