This is the Hollis Marker Buoy with Sling Pouch Dive Signal Marker Available in Orange or Yellow Features: Oral Inflation Quick Dump Valve Comes with mountable carry pouch Hollis Marker Buoy w/ Sling Pouch - Yellow. Marker buoy&';s are floated on the surface during a dive to mark the diver&';s position during drift dives, night dives, mist or disturbed sea conditions