The wood stick spanned with horse hair is called a bow and is used to stroke the strings. Virtually all of the modern-day bows are made of Brazilian fernambuk wood. In the past other woods like snake wood were also used. These woods are still used when constructing historical instruments. Recently, synthetic fibers such as fiberglass and carbon have begun to be used. The results can be astounding and their playing qualities are comparable to good or even excellent bows. Some musicians see a disadvantage in the thinner and higher sound produced by these bows.