We strongly advise the use of this bag when charging Lipos.  The bag will help contain a lipo flare up in case something goes wrong.  Even with the use of this bag, we still strongly advise that you charge your Lipos in an area that if a fire starts, nothing around can catch on fire.  The best method for charging a Lipo is to charge in a Lipo bag placed in a ceramic dish.  This bag comes with a free lifetime replacement if ever used in stopping a Lipo fire.  Simply send back the burned bag from the fire and we will send you a new bag free of charge.