? The In Line Series of Filters, Regulators and Lubricators is an economical way to operate, protect and maintain your air tools. These devices are supplied with female inlet and male outlet threads for easy installation into the tool. This series is designed for applications where standard controls can t be used. ? Protects expensive air tools ? Eliminates any guesswork by automatically administering oil to the tool ? Lightweight and compact ? Clear casing allows users to easily monitor oil levels