What shape must a partly submerged object being towed display during the day to indicate its presence?

A partly submerged object being towed must display a diamond shape during the day to indicate its presence. This requirement is outlined in navigation rules to ensure that other vessels can easily recognize the object and take appropriate action to avoid collisions. The diamond shape is specifically designated for towed objects, making it distinct from the shapes used for other types of navigation signals, which helps maintain safety on the waterways. The use of this shape, along with its visibility standards, allows for clear communication to nearby vessels about the presence and nature of the towed object, enhancing navigational awareness.