Just going over a design for a flash back arrestor. Some people have been asking questions related to flash back arrestors when using a hydrogen fuel cell. So here it is. A very easy technique to implement a simple flash back arrestor using fine bronze wool picked up from a local boating supply store. This will be used in future experiments related to a HHO mini torch, and hydrogen heating applications. There are three known techniques for flash back arrestors that are proven: fine bronze wool, cigarette filter, and a fine (white) fish tank air stone. ** Please NOTE ** 3/8″ Tap is tapered NPT (National Pipe Thread) This is a safety mechanism that is MANDATORY in every HHO Cell design! Safety is our top concern. Keep your set-up legit and you can ignite the gas with-out concern of explosions in your hydrogen experiments. That in itself is a accomplishment. Regards, –sirHOAX–