Wolf Super Endpin

This is my second one of these and I'm still not impressed by the three screws which invariably loosen with playing. I need to tighten them every time, it's part of the pulling the end-pin out routine. It doesn't lock. Using pliers to tighten as much as possible helps but that is really going too far. There is a slot so that you can use a coin or a screwdriver but it isn't deep enough. There are cheaper end-pins which do stay tight but their rubber wears out much quicker. At least with this, the rubber keeps going for many years, the rubber wearing out problem with others is such that when they go, the bass just slides away and this is most disconcerting. Still looking for the perfect one.

I have had two of these. The first dropped off and got lost somewhere between a gig and my car. The second I don't bother using anymore. I think there are two problems with this.
The first is that the three little grub screws and not man enough to grip the end pin and they constantly work themselves loose. I find I am often tightening them.
The second problem is that it doesn't grip a smooth floor that well - its fine on carpets but nothing else. I have bought 2 - I won't be buying a third.
If you play with a very upright stance this could work for you as long as you take care to check its still attached everytime you move the instrument.