Canni mastri (m) (plurale tantum)
(with) definite article: idouble chanter, not linked
Local term used by makers and pipers.
Canni mastri
Sarica, Mario: La zampogna a paro siciliana [Title on 1st text page: La zampogna a paro in Sicilia]. In: La zampogna: gli aerofoni a sacco in Italia (2005), II, p.155, 164 (canne!), 165 (measures).