The Brutes (1970)

Werner and Mike only have one hobby: women. Like two starved predators, they pursue the fair sex and never miss an opportunity to satisfy their instincts. At a kart race they meet lovely young Alice and take her to a gravel pit for a nightly swim. But fun becomes serious and for Alice the night turns into a terrible nightmare. At dawn the full extent of what happened reveals itself, but Alice has no idea that her true ordeal has only just begun.