Okay Energy pre-anti backfire oxyhydrogen flame torch can completely solve the problem of backfire.
It is easy to say that a flame arrester is added between the nozzle and valve which have two functions.The first one is that it works in case of accidentally backfire during operational process.The second one is when the operation is finished to close the valve directly,it can prevent effectively oxyhydrogen flame which is possible to backfire as for the pressure down to zero.