Anybody doubts what I'm saying about dirty, unsterile gear- go read Jerk killers' sticky in the classifieds. And just so you know you take the metal crimp top seal off and with sterile procedure stick in the syringe filter first just outside of where mark would show once re-crimped(there's plenty of room trust me) then after a few drops- you stick in 25g vent needle. Once re-crimped no marks will show once flip top is removed. 25g dont really show after 1 inject anyway in the stoppers on my factory sterilized and sealed vials.