Siphon Spray Wort Aerator
"Another opportunity to add oxygen to your batch of homebrew is when the chilled wort is being transferred from the kettle to the fermenter. If the transfer is taking place through some type of hose or tubing, attaching a sanitized bent pen clip or other device (such as a Fermentap Siphon Spray) to the end of the tubing will cause the wort to spray and splash as it enters the fermenter."
Fits onto 3/8'' OD hose.
This also the same piece that comes with the fermentap sparge arm. Can be used as the replacement if lost or broken.