3D Printer T8 300mm Stainless Steel Lead Screw Coupling Shaft Mounting BracketLead screw:Material: Stainless stellDiameter: 8 mmPitch: 2 mmLength: 300 mmNut:Material: BrassDiameter: 8 mmPitch: 2 mmMounted ball bearing:Material: Zinc alloyBore diameter: 8