金属氧化物避雷器（MOA）是用于保护输变电设备的绝缘免受过电压危害的重要保护电器，它具有响应快、伏安特性平坦、性能稳定、通流容量大、残压低、寿命长、结构简单等优点，广泛使用于发电、输电、变电、配电等系统中。复合外套金属氧化物避雷器是用硅橡胶复合材料做外套，和传统的瓷外套避雷器相比，具有尺寸小、重量轻、结构坚固、耐污性强、防爆性能好等优点。
Metal oxide arrester (MOA) is used for insulation from the important protection of electrical voltage hazard protection of power transmission equipment, it has the advantages of quick response, smooth, stable performance, the volt ampere characteristics of through flow capacity, low residual pressure, long service life, simple structure, widely used in power generation, transmission, substation, power distribution system in. The composite coat metal oxide arrester is made of silicone rubber composite material. Compared with the traditional porcelain coat arrester, it has the advantages of small size, light weight, strong structure, strong stain resistance and good explosion-proof performance.