Select a Product Part NumberIncludesPortFlow R21-03RGWith Gauge3/8"180 SCFM R21-02RGWith Gauge1/4"117 SCFM R21-04RGWith Gauge1/2"195 SCFM R21-06RGWith Gauge3/4"220 SCFM R21-03RWithout Gauge3/8"180 SCFM R21-04RWithout Gauge1/2"195 SCFM R21-06RWithout Gauge3/4"220 SCFM R21-02RWithout Gauge1/4"117 SCFM