Corrugated flexible hose coupling system

A coupling system for a flexible hose with corrugations and an end, which comprises:

• (a) a fitting assembly including:
• (1) an inner fitting with inner and outer ends, a receiver receiving the flexible hose in its inner end, a shoulder projecting radially inwardly into said inner fitting receiver and a female-threaded bore open at its outer end and communicating with said receiver;
• and
• (2) an outer fitting with a male-threaded inner end threadably receivable in said inner fitting female-threaded bore, an outer end, a bore extending between said outer fitting ends and having a bore inner section adjacent said outer fitting inner end and a bore outer section adjacent said outer fitting outer end;
• (b) an expandable washer having an expanded, first position passing the hose therethrough and a constricted, second position clamping said hose between corrugations thereof, said washer being positioned within said fitting assembly in engagement with said inner fitting shoulder in its constricted second position;
• (c) a backer ring slidably receiving the hose and positioned within the fitting assembly in engagement with the expandable washer;
• and
• (d) a sealing ring comprising an O-ring engaging the backer ring, the hose and the outer fitting inner end, said O-ring including sealing means for forming a seal between the hose and the fitting assembly, said 0-ring being compressed between said outer fitting inner end and said backer ring and said backer ring spacing said O-ring in a groove in the corrugated hose.