This design is an adaptor meant to use a syringe to pipette very small amounts of liquid precisely with a micromanipulator.
The idea is to take a 1ml syringe with a very thin nozzle (i use hot drawn capillary tubes stuck on conventional 25G neddles), fix it on a micromanipulator and use a micrometer to push on the piston. I personally use it to handle UV glue used a binocular setup.
The design use a 13mm micrometer sourced from Taobao (+-3USD https://detail.tmall.com/item.htm?_u=q209fqk4rgbe24&id=667567963046&spm=a1z09.2.0.0.4f912e8d8SU6bX&skuId=4978134094594) After a quick search the same model seems available on other platforms. I advise to dismantle and wash with acetone to remove the grease before use. It will reduce the life of the device but also the friction and the vibrations you will generate on the tip.
My model also uses a M3 screw and heat set insert, as well as a 2mm metal rod for the pivot (a long M2 screw could do the trick)
This design is not meant to handle more than 0.1 or 0.2ml (i often only use 0.01ml), I can easily aim for targets about 20 to 30 microns with my setup but the precision will depend on your micromanipulator (the stiffer the better) and binocular. You may also need additional custom parts for the connection. The print will require supports.