I have rescued cats for years and currently have 3 inside and a feral colony of 5 outside. I use these syringes to feed cats who need to be syringe-fed. I do wash them and reuse them until the rubber on the end of the plunger swells and will no longer fit in the syringe, usually 5 or 6 uses. As the plungers begin to get a little tight, I dip the rubber plunger in a little canola oil and they work fine until they just won't fit any more. These syringes hold the amount of food I need, but are too expensive (for me) to replace after a single use. I have absolutely no complaints given that I'm asking more of the syringes than they were designed to do, and am grateful to have found them since I haven't been able to find a multiple-use syringe in the size I need.