28 will draw but it's slow. Probably 2 min per mL. Heat your oil in a hot cup of water first to speed it up. Also to help draw pull back an empty plunger to the amount you want. Then cut a toothpick or piece of ridgid wire the distance from the top of the barrels finger holds to the plungers cap. Now lay the vial on its side, insert pin, draw, and put your new stick or wire in between the barrels finger tabs and the plungers cap. You then no longer have to hold it while it fills and it gives you the exact dose every time
