Just like the ones you receive from the vet at a more reasonable price! I like the 5/16" short tip for my cat because it's much easier to insert versus a longer tip. 31g is a thin needle, my pet does not even notice it going in. 0.3ml is a smaller barrel so I can more precisely measure the insulin doses. The only thing you need to make sure is that your medication is to be administered in a U-40 syringe (which this is) versus a U-100, as this affects the dose measurement. Highly recommend.