Yeah.. I'm not in charge of the supplies in which my mom gets for Sammy I'm just the one who takes care of him and tries to inform my family on what to get him

The ones my mom keeps buying are the ones from Walmart and they did not have U40 so she ended up getting one that goes by one unit's so I really only know that in between each unit is 0.50 ( if I'm correct) and you are right it would be so much easier buying the U40 and it is what Vetsulin is supposed to have.
Ill try and talk to my mom about buying the syringes you gave in the links, there surprisingly a pretty good price. For now what should i do on dosing? I know my mom is probably going to wait off till we are almost halfway done with the box we have now before ordering new syringes.
(This is the current syringe)