Stereo input “si” design, Patent-pending integrated woofer/baffle assembly, Mica-filled polypropylene woofer cone – Niles Audio OS6.3Si User Manual
Page 4: Butyl-rubber woofer cone surround, Dual-voice-coil woofer, Dual ultrasilk, Dome tweeters, Stereo-imaging tweeter array, Weatherproof engineering, Advanced material science
