Creality CR-10S bed leveling knobs for a SainSmart reprap purchased February, 2018. Other knobs were slightly off, so I created these using Fusion 360 and test printed them several times until the fit was perfect (for my printer at least).

The wheels touch the bottom of bed bracket when tightening so that they feel snug instead of loose and too easy to turn. Previous knobs would turn when brushing or bumping them. These knobs should slide into seat very precisely and should not require any actual muscle to insert. They are held on by the inside (top) bevel.

Note: Due to the fast updates and resale modifications, I recommend measuring your current bed knobs and comparing to the files before printing.