<div class="htmlview paragraph">Cocktail shaker cooling is the commonly used term to describe heat transfer in a reciprocating hollow cylinder partially filled with a liquid. The sodium filled valve is a widely used application of this heat transfer concept.</div> <div class="htmlview paragraph">This paper presents information that may be useful in the design of cocktail shaker cooled pistons and valves. The design data are presented in nondimensional form using parameters typical of conventional convective heat transfer correlations. An illustrative problem for a piston is presented to show the application of the design data.</div>