Niche Fpp is the original fluoropolymer heat exchangers manufacturer and still the only company that makes FEP and PFA tubing for Shell and tube heat exchangers. Heat Exchanger Types: 1) PV-4 Series 3" Shell- Small, inexpensive heat exchangers with three-inch shells, ideal for low flow processes. 2) 30-Series Mid-Size 4" Shell- Medium-size heat exchangers with 4-inch diameter shells, suitable for typical applications. 3)30-Series Model 218, 525 and 1000 - Large heat exchangers with 10-inch diameter shells, designed for large volume processes. 4) 900-Series Large Capacity- Niche largest heat exchangers with 14-inch diameter shells, prov