Best to fill empty cartriges immediately, ended up getting 8 full ones , just be smart with it and you'll be just fine ;)
I saw this and thought wow. I can refill and not waste. The way you fill it is tricky. As the syringe will hold some inside, you have Yo close it out or it will leave when stored. Some how the Oil leaks. I’ve done it three times and I’ve wasted half of what’s inside the syringe. It’s not worth the mess and you end up wasting most of it.