This is a slider that is designed to run inside the T-track of an Einhell RT-TS-920 table saw. The hole on the bottom is a tight fit for M6 hexagon nut.
Two versions are available: one that runs free (can be used for creating sleds), and one that is lockable (can be used for clamps or featherboards).
I recommend printing with at least 2 mm walls. You can print without supports, though you may need to clean up the screw hole a bit after printing.