Description:  NEMA17 Stepper Motor with 400mm T8 Lead Screw Mounted Ball Bearing and Shaft Coupling.     Specification:  Lead screw:  Material: stainless steel.  Diameter: 8mm.  Pitch: 2mm.  Lead: 4.  Total Length: 400mm.  Screw nut:  Material: brass.  Diameter: 8mm.  Pitch: 2mm.  Lead: 4.  Mounted ball bearing:  Material: zinc alloy.  Bore diameter8 mm: 8mm.  Total length: 55mm.  Height: 29mm.  Shaft coupling:  Material: aluminium.  Shaft: 6.35 x 8 mm.  Length: 25 mm.  Diameter: 20mm.  Motor:  Voltage: 24V.  Step angle: 1.8°.  Accuracy of step angle: ±5%.  Accuracy of resistance: ±10%.  Accuracy of inductance: ±20%.  Insulation resistance: 100mΩmin 500VDC.  Radial clearance: 0.02Max.  Axial clearance: 0.08Max.  Radial maximum tolerance: 28N.  Axial maximum tolerance: 10N.     Features:  3D printer T8 400mm Stainless Steel Lead Screw + Screw nut + Mounted ball bearing+Shaft coupling+Motor.  Screw mainly use for Stepping motor driving guide rail,machine tool, and other equipment.  Screw without processing, direct connected to bearing.  T shape design, make of high quality stainless steel material.  Easy to install and convenient to use.  Fine producing and practical.  Suitable for Industrial automation equipment, stepper motor rails;  Fit for 3D printer; engraving machine; XYZ module; slider; lifts ect.     How to install:  1. Put screw nut into the lead screw.  2. Then the 2 Mounted ball bearing separately install at both ends of the Lead screw.  3. According to the size of you need to adjust the distance between the nut and Mounted ball bearing.  4. Put shaft coupling into the Lead screw beside the Mounted ball bearing.     Package Included:  1 x 400mm Lead screw.  1 x Screw nut.  2 x Mounted ball bearing.  1 x Shaft coupling.  1 x Motor