The two-tank upgrade is avail­able in two con­fig­u­ra­tions — either aux­il­iary tank braces only or the aux­il­iary tank braces plus an extra propane hose assem­bly (plumb­ing) to con­nect the two tanks togeth­er. The aux­il­iary tank braces make it pos­si­ble to car­ry two propane tanks on the tool cart; the extra plumb­ing makes it pos­si­ble to use both of those tanks simul­ta­ne­ous­ly. Without the extra plumb­ing, when a tank runs low or starts to freeze you will have to inter­rupt your flam­ing and switch tanks. With the extra plumb­ing you dou­ble your unin­ter­rupt­ed flam­ing time.