Source for flashback arrestors

Western Enterprises flash- McMaster-Carr Western 2 

Catalytic recombiners also require a filter, located after the second flashback arrester, to collect the water formed by the catalyst. 

Most filters on the market have either aluminum or zinc bodies and polycarbonate bowls. These materials are very reactive and do not stand up well under exposure to KOH. Either a stainless steel filter or coalescer should be used for this purpose. 

We used a brass body filter with a polyurethane bowl as a low cost alternative to purchasing another stainless steel bodied filter. This worked well for the experimental purposes, but stainless steel is the appropriate metal for this component in this type of system. 

You can fabricate filters yourself. Please note that filters need to be placed as shown in the photographs with the bowl on the bottom for water collection. 

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