Seventy years after they were first described, the function of Traful Instruments is still uncertain. From their morphological design and the associated environmental and archaeological contexts, we postulate that they are part of a specialized «composite instrument» for fishing. While their characteristics are unique in the context of the lakes and rivers of North-west Argentinean Patagonia, similarities were found with the line-weights which are widely distributed in Magellanic marine contexts.La funcionalidad de los Instrumentos Traful es incierta luego de 70 años de su descripción. A partir de su diseño morfológico, el contexto ambiental y arqueológico asociado, postulamos que son parte de un “instrumento compuesto” especializado en la pesca. Si bien presentan características singulares en el contexto lacustre y rivereño del interior de la Patagonia noroccidental argentina, se asemejan en cuestiones básicas a los pesos de líneas marinos de gran distribución magallánica.