Attachment to manually hold in the dispenser button on Igloo water coolers, specifically the 5 gallon size.

I use this Igloo container to brew Kombucha in prior to transferring to a keg for secondary fermentation and conditioning. This device allows you to "press and hold" the dispenser button to easily drain the entire contents into another vessel.

(Thanks to Mcmaster-Carr - the thumb screw model is directly from their website. The PN is 92625A130.)