Hegar Sound - 5 to 6 mm

The dual-diameter ends on this single sound make it perfect for gradually increasing size without needing a full kit. I've used it a few times now and it slides smoothly with proper lubrication. Exactly what I needed to try before committing to a larger set.

Finally, a single size so I didn't have to buy a full set just for this one. The tapered ends make it easy to start with the smaller diameter and step up.

Was a little unsure about ordering just one size, but the 5mm end worked perfectly for my first attempt. The two different diameters on one tool made sense once I actually held it. Glad I didn't have to buy a full set.