The Scottish smallpipe is a bellows-blown bagpipe developed from the Northumbrian smallpipe by Colin Ross and others to be playable according to the Great Highland Bagpipe fingering system. It has a parallel bored chanter, most commonly pitched in A, although any key is feasible; D, C, and B flat are the next most common keys. They are most commonly unkeyed, but occasionally G sharp, F natural, and C natural keys are added. It is possible to add enough keys to produce a two-octave chromatic scale, but this is rarely done. The present writer cannot think of any prominent piper using such a set. The drones are set in a common stock and are tuned an octave below the tonic, the fifth or an octave below the fifth (a few players choose to tune this to the fourth instead), and two octaves below the tonic. It is perhaps the youngest bagpipe with any popularity, having only existed since its invention in the early 1980s. It is however extremely popular, particularly with Highland pipers, many of whom keep it or a Border pipe as a second instrument. Mouth-blown versions are available, but it is difficult to produce quality tone from these instruments due to the reed's delicate construction.