This new double row version of the Tre35 features 69 individually hand-tied bars with TreeWorks' unique design that allows each row to be played separately. A long sweep to both rows delivers a full, dramatic sound, while playing a single row provides a more modest flourish. For live performance where your sound requires greater strength and resonance; Classic Chimes utilize our T-6 tempered, custom aluminum/ titanium alloy bars. (.375" diameter).