This document provides specifications and application information for Thorne & Derrick's self-regulating heater cables. It describes the standard overjacket and metal braid construction, stranded copper conductors, self-regulating conductive core, and thermoplastic elastomer jacket. It explains the principle of operation where the parallel circuit wires apply voltage along the cable to generate heat proportionate to surrounding temperatures. The document lists performance ratings and power output ratings in watts per foot for different cable models and temperatures. It provides guidance on circuit breaker selection and notes for various voltage and installation scenarios.