These clamps are used on any fitting with a collar to engage the forward gripping fingers of the interlocking clamp. However, they are most commonly used on ground joint females and male collared nipples. Smaller sizes provide a safe and economical securing method for universal hose ends. The forward gripping fingers engage the collar preventing the shank or stem from pulling out. Tightening the bolts secures the clamp around the O.D. of the hose.