Comparison : Item # HTN-74, CGA-590 Nipple-Handtight Inlet
Item # HTN-74P, CGA-590 Nipple-Handtight Inlet
Item # MNP-188, CGA-590 Nipple-Threaded Inlet
Item # MNP-189, CGA-590 Nipple-Threaded Inlet
Item # MNP-190, CGA-590 Nipple-Threaded Inlet