Halo Cartridge Filling Blocks

 Filling a 3mL cartridge by hand — holding it flat on a counter while slowly pushing liquid through the luer lock — works, but it's awkward and spill-prone. The Halo holds your cartridge upright and level on any surface while you fill, freeing both hands for the syringe and letting air vent properly through the luer lock without creating back pressure.

The Standard and Specialty Halo are the same size and fit the same 3mL short-stopper cartridges — pick whichever color you like.
For research purposes only.