Check that no-one has used it in the past, not screwed it in far enough and then bent the shaft of the male, eyed part (no sniggering at the back please). That's what I discovered when I came to need to use mine. The female part in the car's frame is angled divergent to the long axis of the car so when a tow is attached it is unlikely to be in line and there is a tendency to bend the shaft and presumably to cross thread it beforehand... perhaps I was unlucky but mine was unusable; cue lots of manoeuvring [finally got the spelling right] and slings by the AA man.