We developed this filter spout for our make it yourself DEF Kits. We’ve found that it does a great job catching sediment. This is our standard size cap DEFSPOUT that fits our 1 gallon jugs (and most retail DEF 1 gallon and 2.5 gallon containers that use 38/400 caps) with a fine stainless mesh (100 micron) filter installed in the tip. The filter and all other components are compatible with DEF. The DEFSPOUT with filter removes sediment while dispensing DEF from jugs into your vehicle tank and works best with vented jugs. Can significantly extend the life of your vehicle’s DEF system Filter. The DEFSPOUT is flexible and tough enough to be tied in a knot without damage. Rinse with clean tap water from the tip end after use to flush sediment from the filter.