CareLiving Insulin Pen Needles 31G 8 mm (5/16"), 200 Count, Universal Fit Compatible with Most Pen Injector Device, Ultra-Thin for Comfortable Insulin Injection

V1 - Exposed needle tip, generally inexpensive, reliable V2 - Hidden needle tip, a bit more expensive, reliable V3 - Updated V1, but much more expensive, kinda reliable V4 - Cheap "luxury" look IMO, they all do the same shit. The only real difference is the needle is hidden on the V2, and some people may like that. As for pen needles, I've used dozens of brands. They're all the same IMO. I use these: https://www.amazon.com/dp/B0DHKNT7SB They're the cheapest you can find, and they work the same as the expensive ones.