This is a simple little block that allows you to use a Nimble on the Geeetech i3 clone.
It takes the place of the extruder. Simply mount the block on the metal plate, screw the hot end in and adjust the height until it is just touching the Nimble.

One of the most simple adaptors for the Nimble.

The Nimble Extruder
With an installed weight of less than 27 grams on your carriage/effector the Zesty Nimble is smallest and lighest extruder you can buy, it has ample torque and is installable in multiple orientations.

The Nimble is available at: https://zesty.tech