In a sense you're right - I only have good faith that the gear is sterile. But in the end, it must of been sterile b/c if it wasn't sterile I would've encountered some type of problem somewhere along the lines of going through 25 ccs of it - at least, I think I would've. It felt fine throughout the use of the vial, including smooth painless injects, no discomfort afterwards or any adverse side effects or annoyances which I think would be noticeable with contaminated gear. It looked, felt and acted like any and all sterile gear I've ever done so I'd bet it was sterile. Maybe I just got lucky. Anytime we pin anything there is some type of risk involved. Unless we stand on the factory/lab floor and watch our vial/product get made, in the end all we have to go on is reputation and good faith. Luckily, I've yet to experience non-sterile gear over the course of dozens of cycles throughout the past 15 years (knock on wood). Hope I didn't just jinx it.