... the carbon desposit, it will not dissolve the inside metal of engine too, this product’s ceramic components ... we recommend you can drive on the low-grade for the initial stage, then improve slowly, about 15 ... best.After installation, keep no moving for 8 hours, then drive for about 1 hour to reach the fuel ... . 10.packing:11,more product detail: China high quality powerful magnetic fuel saver for car