Sonor KS40L Chime Bars, Ton C3, Metallophone, type tenor-alto, fundamental tuning, grey special alloy metal bars 40 x 6 mm, white resonator per chime bar made of shock-resistant RESOPHEN, (unit 1 chime bar), The different between Chime Bars - Metallophone KS 40 L and Chime Bars - Xylophone KS 40 PO is the tone duration and tone colour. KS 40 L sounds long and warm, KS 40 PO sounds short and concise.