yup yup...i had a 20ml multiuse vial of test cyp and the rubber stopper got beat the fuck up after like 10 pokes. there were pieces of rubber floating in the vial. last thing i wanted is one of those pieces injected into my glute.
so...i ordered a filter...drew out all the oil and slowly filtered it into a fresh sterile vial using one of those filters. thats what these filters are used for.
just as a side note. i lost about 1ml of oil in the filter. luckily i had an extra amp laying around of some test E (schering) that i mixed into it so that I can keep my quantities the same.