This new product pack we put together is just perfect for anyone trying to tune their airsoft gun. If you are testing and tuning and swapping springs, adjusting pressures or anything else that is modifying the power of your gun you need this tuner pack. You will have all 4 of our heavy weight bbs right there in a smaller quantity. So get this tuner pack, find which weight works best for your platform and then come back for a full bag of the weight that is perfect for you.