A torque arm restraint is provided with a body having a bore including an axis and an arm extending from said body transversely to the axis and is adapted for resisting torque applied to the fitting of a liquid storage tank, and is configured either for mounting on a fitting or as a component of the fitting such as an outlet fitting mounting a pipe and extending from the wall of the tank. A tubular body permits passage of instrumentation or liquid therethrough and the arm may have an abutment surface positioned proximate the inside surface of the tank wall, either in engagement or in spaced relationship, whereby the arm resists torque applied to the fitting exteriorly of the tank. The body may include an attachment member which is adapted for mounting to a tank fitting, and may be coupled to a pipe within the tank.