Since one pellet is 20mg, you cant get 75.mg from one. One comp-H cartridge contains 100 pellets, that are 20mg each which of course equals 2000mg of tren. If you use that with a 2gF kit, you will end up with 23-25ml of final product that is 75mg/ml.
Lets say your total yield is 25ml at the end of the conversion process. 2000mg (100pellets x 20mg per pellet) divided by 25ml = 80mg per ml (Of course there has to be some loss during the conversion). So each pellet would make up approximately 1/4ml of actual fina. Was this the question