perfect replacement for the evaporator side of a phase change \H2O chip chiller (with a bit O work)
http://www.stpats.com/chillers.htm
all copper (Insulated after the fact)
excerpt
Why is convoluted copper so much more efficient than straight sided copper?
1) Increased surface area
2) Increased turbulence of BOTH the wort (inside of convoluted tubing) and the chilling water (outside of convoluted tubing)
3)Convoluted copper is made from copper with greater thermal conduction than the copper used in soft refrigeration tubing.
trick units only $99