Stir shaft couplings for connecting glass or metal stir shafts to the adjustable chuck on an overhead stir motor. Compression connection is secured to various OD shafts via an Allen screw coupling. The Codes -22 and -24 are complete pass-thru assemblies that enable height adjustment on stir shafts when using overhead stir motors with pass-thru shaft openings such as our Caframo 13565 & 13566 and our Ika (13514, 13516, 13517 & 13518) product families.