I have started refilling my cartridges for my 801 pen style and am amazed at how much it will hold! I start by removing the stuffing and adding 15 drops, replacing the stuffing and topping off with around another 5 or so drops until it saturates up to the top. After about 5 min. it settles in and I can add about another 20 drops! After vapping out a battery charge I refilled it another 17 drops! Im using pure uncut Johnson Creek juice and really like the way it works. Good smoke without too much of a throat hit and the Original tobacco flavor is delightful.