A bell ('cow bell') attached to the timbales-stand or held in one hand, played with a wooden stick. In Salsa it often plays a very steady rhythm (1st and 3rd beat of the measure).
Vallenato actually refers more to an orchestration than a specific rhythm. A traditional vallenato group consists of an accordion, a scraper called a guacharaca, and a hand drum called a caja ...
Typical Salsa drum set consisting of 2 tuneable drums (different in pitch), 2 cow bells ("campanas"), cybal(s) and possibly woodblock. Played with two sticks.