3mm to 3.17mm Shaft Couplings L26xD10 Flexible Motor Rigid Coupler w Spanner – 3mm to 3.17mm (3mm to 3.17mm – Aluminum). Description: Fixed Couplers are used to Connect Stepper Servo AC DC motors to Ball screw or Lead screw they are widely used to build CNC Router, CNC Plasma, CNC Mill, CNC Laser and many automation machines. Widely used in hardware,molds, and the occasion of the mechanical transmission. Specification: Material: Aluminum Color: Silver Tone Suitable For: connecting two axis with different diameters, can also be connected with a motor axis, or connecting shafts of different diameters. Between the transmission member can do both screw can do model remote control boat propeller shaft and the motor power. Connection diameter: 3mm to 3.17mm Top Thread Size: M3 Through Angle:180 Degree Dimensions: 10 x 26mm/0.39 x 1.02 inch(D*L)) Note: The color of the item may vary slightly due to photography and your own computer Package included: 1 x Motor Rigid Coupling 1 x Hex Head Spanner 4 x Screws While we aim to supply accurate product information, it is sourced by manufacturers, suppliers and marketplace sellers, and has not been provided by Overstock.