As the name suggests, when they are molded a clip swivel is inserted into the lead while it is still hot molten.
There have been several shapes over the years, but a teardrop shape seems to have won through. They are a very versatile sinker and can be used in a variety of fishing types.
Ranging from 28g (1oz) to 567g (20oz), there is a weight to suit most needs.
They are excellent on dropper rigs and for surf casting and they are quick and easy to use.
More or less weight can be added or removed as required, very simply.