SuperFlash flashback arrestors are UL and BAM approved, 100% tested for reverse flow, leak integrity and flashback protection with actual flashbacks, and contain a built-in 100 micron inlet filter, reverse flow check valve, 3-5 micron flame barrier, and a thermal shutoff valve in ourpoint of supply models. So you can be sure that not only are you getting enough gas flow, you are getting the highest quality safety device available. SuperFlash flashback arrestors are the worldwide leader in quality and functionality. DO ALL FLAME BARRIERS PROVIDE THE SAME LEVEL OF PROTECTION? No, all flame barriers are not created equal. Flame barriers can be made of different materials and have different micron openings. The flame barrier needs to be made a material that will extinguish fires and have the right size openings to allow gas throughbut not a flashback. If the micron openings are too large or the material is not correctthe flame barrier will not stop a flashback. SuperFlash flashback arrestors