These wagglers are widely used on the continent to make plumbing up easier especially when using a slider waggler setup.
These have a small loading in the base and can be used to replace your slider float once you have shotted it up as the thicker stem and 'underloaded' float mean a large plummet can be used to gauge the depth. Some anglers use a second rod set up with this float and a large bomb to plumb up accurately.
Please not that this float will only work if you use a silicon adapter on the base of your slider float as you cannot swap it without.