1/2/5pcs Thread Adapter Male to Male Bolt M3 M4 M5 M6 M8 M10 M12 M14 M16 to M20 304 Stainless Steel Double Head Transfer Screw Bolt Full Thread (Size : 1pc M10x25-M16x25):
Uxcell M10/M12 to M6/M8/M10 30mm Long Double Male Threaded Reducer Bolt Screw Fitting Adapter 6 Pack - Walmart.com
10pieces/lot M6 To M10, M8 To M10, M10 To M12/m14 Threaded Hollow Tube Adapter Inner Outer Threaded Coupler Conveyer Adapter - Pipe Fittings - AliExpress