The Oasis® Humigel™ Replacement Kit contains a small package of Humigel™ crystals sufficient to refill 4-6 times, instructions, a .15 cc scoop to accurately measure the amount of crystals needed and a 10cc. syringe. We feel that including the syringe in this package will both reduce crystals loss and encourage the use of distilled water for filling the humidifier. We offer this for the low price of $4.95. The dry crystals should retain their potency for five years or more. One replacement kit should last for several years even if you have several humidifiers to refill annually.