When attached to the top of Snyder Column, unit is designed to recover solvent normally lost during Kuderna-Danish Evaporative Concentrations. PTFE stopcock (1:5, 2mm bore) provides option for total reflux or takeoff. #7 Ace-Thred on side arm accepts tubing 6 - 7mm O.D. 5029-10 Nylon bushing and FETFE O-Ring supplied with adapter.