Focal Polyglass 100VRS 10cm component speakers Focals Polyglass 100VRS Slim component speaker systems use precision craftmanship & advanced materials to make a strong sonic impression. & these systems include shallow-mount woofers thatll fit in the factory speaker locations in a wide range of vehicles. 2-layer woofer cone The Focal Polyglass 100VRS system features a 4" woofer with a Polyglass cone thats created by depositing a layer of hollow glass microbeads over a layer of cellulose pulp. This unique material combines the warm sound of cellulose with the incredible strength of glass, for a cone that responds rapidly with extremely low resonance. A butyl rubber surround helps control cone movement & promotes high power handling. The zamak (zinc alloy) basket provides a non-magnetic, non-resonant housing that wont color the sound. Unique tweeter design Focal designed the aluminum/magnesium inverted dome tweeter to disperse high frequencies eve