Mueller Accu-Therm HeatX. All stainless construction.  104 plate, dual stage heat exchanger capable of chilling 10bbls of beer in approximately 25 min (water and glycol temp dependent).  1.5" TC connections on all inlets and outlets.  Expandable to be able to hold more plates for faster chilling if needed.

We recently replaced this unit with a larger unit when upgrading our system.  Worked well for 5 years without issue, we just needed a larger unit.