Boy, does this re-open a sor subject!
Klein used to offer their tools with an optional "high dielectric" coating- yet insistsed that "high di-electric" in no way implied any insulative value at all!
If you wanted tools that admitted to being designed for working on live circuits, you had to import some German tools, that met DIN specs. Today, the tools Klein sells for this application appear absolutely identical to those German tools.
One requirement of the DIN standard is that there be two differently colored layers of insulating material; the idea is that this will make it easier to spot any damage to the outer layer.
The vinyl dip on tool handles is generally there for reasons of comfort only. While they may -or may not- help protect you from a shock, there is generally another place for electricity to go. That's why we've all turned a pair of dikes into strippers at one time or another- and generally haven't felt a shock when we did so!
For what it's worth, the US Navy generally has tools without the dip on the handles, as a means of encouraging personnel to de-energize equipment before working on it. No, I'm not making this up!
