Apologies, Wendy .. I missed your message. I’ve got a very sick IBD cat, a hypercalcemic cat, a cat which recently had two hospitalizations/surgery for urinary blockage, and Mia. Gets a little crazy here at times! I found one drop places the black plunger tip at the bottom of the baseline mark. Later, found moving from the .5u mark to empty, counting drops, also put the plunger at the same baseline mark for .1-.15u, dependent upon the syringe. They aren’t consistent across the board. So, I now question how much she is actually getting from shot to shot. Could be one drop, or could be .1u. Not sure. Tried the method of letting the vacuum draw a drop, and couldn’t get it to work. Also, the drops were measured by twisting the plunger until one fully formed and broke away on the needle tip. They’re pretty big drops. Not a precise method, I realize, but I just don’t have enough energy to take it to calipers. I welcome other suggestions. Mia has other major body issues, and I am just trying to keep her quality of life comfortable and healthy enough for her time remaining. Thanks for checking in!