Comparison : Item # 1-1 FBZ, NPT Male Connector for fractional tube
Item # 1-2 FBZ, NPT Male Connector for fractional tube
Item # 1-4 FBZ, NPT Male Connector for fractional tube
Item # 2-1 FBZ, NPT Male Connector for fractional tube
Item # 2-2 FBZ, NPT Male Connector for fractional tube