The most direct way to cool the beer in your horizontal cask is to cool the beer from the inside of the cask. Used in conjunction with an insulation jacket the probe is a stainless steel tube element which is put into the cask through the shive hole in the cask.
To use, you need to remove the existing cask shive after venting the fresh cask and then feed in the probe (sterilize first). The integral plastic shive will then seal this into the cask (with a gentle tap).
Tube size is 5/16” diameter so very easy to pipe onto up using John Guest or similar push-fit fittings.
Adjustable for 4.5 to 18 Gallon Casks.