61FHM mid-woofer was designed for outdoor applications, yet it will shine in hi-fi home and studio applications as well. Optimized ferrite based magnetic circuit with good air-venting features ensures long lasting performance. Our engineers have chosen polypropylene cone with rubber surround for this model. Both of these components are produced with UV stabilizers. Furthermore, REDCATT state of the art adhesives and dispensing techniques ensures waterproof seals in all weather exposed glue joints. Sealing to the exposure can be guaranteed by EVA gaskets or based upon a request by Form In Place Gaskets. The audio system designers can rest assured we have extensively tested this product with UV exposure, salt exposure and waterproofing. The extended mid-frequency response allows the systems to be used with higher resonance frequency HF units. For the best performance in the audio systems, we recommend usage in vented enclosures.