3mm x 3mm Rigid Shaft Coupler CNC Stepper Servo Motor Coupling Clamp Type $7.99 Equipment/Supplies Type Shaft Coupler MPN 100160 Brand CNC.BZ Model 3mm x 3mm condition New New Precision Aluminum Rigid Shaft Coupler 3MM x 3MM Clamp Type Outside Dimensions: Diameter 20mm, Length 25mm