The design of our Flex-Drive stirrer coupling eliminates the need to use rubber hose or universal adapters to attach your glass stirrer shafts to overhead motors. Coupling incorporates a 3in long epoxy coated spring to compensate for misalignment and to help isolate breakage. Lower end of coupling has a Celcon compression nut which secures the glass shaft to the coupling via a silicone rubber insert. The silicone insert, along with the knurled compression nut, permits hand tightening of both ground and polished shafts. Top epoxy coated bushing is fitted with an allen screw and will accept 5/16in O.D. stirrer motor shafts. Adapters to 1/4”, 3/8" and 1/2” are also supplied to permit use of coupling with stirrer motors having different drive shaft diameters.