SoundTube SM500i-II-WX 5.25-Inch Surface Mount SpeakerThe SoundTube SM500I II WX has one 5. 25 inch (133 mm) polypropylene woofer and one 1. 0 inch (25 mm) convex titanium tweeter with FerroFluid cooling. SoundTube's WX Weather Guard technology utilizes a dual layer hydrophobic material inside the speaker grille to keep water from the drivers and internal electronics in even the most extreme weather conditions. The SM500I II WX utilizes the patented ZeroReflection enclosure technology for optimal sound