Abstract: A swimming aid training device to improve swimming technique, comprised a buoy assembly and a fin assembly. The buoy assembly is shaped to fit onto the calf area of a swimmer and has a substantially rotated H-shape. In the preferred embodiment, the buoy assembly is made of resilient and buoyant material. The fin assembly comprises fins that are substantially parallel with respect to each other and are kept in a spaced apart relationship by a frame. The swimming aid training device may be configured for volumetrically efficient transportation and/or storage.