Firestone rotary evaporators 

Constructed of glass, PTFE, and nylon. Operates without metal devices. Hollow glass tube (10 mm o.d.), with joint at one end for flask and holes drilled near center for vacuum. Attaches to any laboratory stirring motor. Tube turns inside PTFE bearing, threads held in by nylon bushing, saddle O-ring, and lock nut. 2 mm straight-bore stopcock attaches to drying tube or McLeod gauge. One arm of 4 mm bore double stopcock attaches to dry ice trap and vacuum line; other arm is for easy vacuum release and can be connected to a trap. Complete set includes joint clamp.

NOTE: Designed by Dr. Raymond Firestone, Merck, Sharp & Dohme Research Labs (U.S. Patent applied for).