Superior PTD Pure-Titanium Domes with Unique Controlled WaveGuide Faceplates deliver smooth, clear, extended response. Ferro-fluid cooled and damped. Superior ICP Injection-Molded Co-Polymer Polypropylene Cones. Oversized magnets and superior motor structures ensure a very detailed, authentic midrange. Superior PolyGlass Mineral-Filled Reinforced Enclosures. Fully sealed (no ports) for protection against the outdoor environment â€¦ even under adverse weather conditions! Weather, Water, UV-Resistant Aluminum Grilles stainless steel / brass hardware, gold-plated binding posts and stainless steel / polymer mounting brackets..