<b>How to use</b><br> 1.Just press it on hard<br> 2.Best important step: a sound “POP” is a key point to make sure spill free.<br> <br> <b>Uses in different occasion </b><br> White inner inset, air-tight foam, dust-cover could be taken off as you need.<br> 1.If you put the caps on probe type dispenser, the caps would be stick with the probe instead of float around in the water.<br> 2.If you use it in the water bottle on the top rack or with water pump, you can take off the inner caps for reusable.<br> <br> <br> <b>Package included</b><br> 20×3 & 5 gallon water jug cap<br>