A single jacket hose has one woven polyester jacket glued to the outside of the rubber liner. So a single jacket hose can protect the rubber liner fine if the hose is only being used occasionally for light use, for a temporary job or on a non-abrasive surface such as grass. Single jacket hose can save cost in the right situation. It can also save weight which can be important in applications such as fighting forestry fires where the hose is often carried on foot by firefighters. It is a misconception that forestry or wildland fire hose is extremely durable, if you need durable hose you need double jacket hose.