BIQU 3D Touch (BL Touch Compatible V3.1 Auto Bed Level Sensor for Ender 3 5 CR-10 SKR V4.2.7 Board - RRP £38.99. BIQU BL Touch V3.1 Auto Bed Levelling Sensor – Precision Upgrade for 3D Printers. Full installation instructions and firmware files available from the BIQU GitHub or Creality community. ).
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