The Garden Oasis GO4 enclosure is more than twice as strong as other outdoor speakers, thanks to their thermoplastic shell and mounting stem. Durable, weatherproof thermoplastic is water-resistant and withstands extreme temperatures up and down the thermometer. Its high crystallinity, with high UVB resistance, keeps it from cracking over time, making it the best material for a long, trouble-free life out-of-doors. Each satellite speaker includes an off-season cap for extra protection from the elements.