Lift up tabs and spin wheels freely for big adjustments, and click the wheels against the tabs for small adjustments.
These let you release the tension on the bed springs and minimize warping while still holding a consistent level over time. Pretty much set it and forget it bed leveling. When you do have to level, the clip thumbs click against the wheels, making for easy and consistent adjustments.
You can even switch from glass and glue to spring steel PEI, without any need for auto bed leveling systems like a BLTouch. They really made a magnetic spring steel PEI bed work great and carefree.
Put one in each corner. Install on top of bed carriage facing downward with springs/spacers on top of the clips, so that the thumbs interact with the wheels.
Printed in High Temperature ASA so no worry of warping even if you place your printer in an enclosure.
(Set of 4).