Combination Square, 12" 4R, Starrett

The lock bolt on this square feels solid and holds the blade tight without any wobble, which is exactly what I needed for precise layout work. The spirit level is a nice bonus for quick checks, and the whole tool has a nice heft to it.

The engraved markings on the blade are crisp and easy to read, and the scriber is a handy bonus. This is the most precise square I've owned.

The cast iron head feels rock solid in hand, and that reversible lock bolt makes switching between inside and outside measurements effortless. The spirit level came in handy more than I expected, and the photoengraved blade is still crisp after a week of shop use.