this disclosure relates generally to hose couplings useful for mining applications , more particularly to a fluid coupling capable of generally fully tightened by hand , including a visual lock for visual indication and safety when in a hand - tightened position . the coupling generally includes a male portion , a female portion , a retaining member and a locking member . the male portion passes through the retaining member , and the retaining member threadingly engages the female member . the locking member prevents unthreading of the retaining member from the female member .