10 Gauge Extension Cord by Watt's Wire: Designed to safely handle up to 15 amps, this 15 amp extension cord is perfect for high-powered tools and equipment in outdoor environments. Outdoor Extension Cord SJTW: Our heavy duty power cords are made with an SJTW jacket which is suitable to temperatures from -40°F to 130°F. This waterproof extension cord can be used in rain or shine. *Keep connection points dry.