• Atlantic whelk shells, knobbed whelks, measure between approximately 7 inches in size.  
• The Atlantic whelk shells, knobbed whelk, Busycon carica, is a species of very large predatory sea snail, or in the USA, a whelk, a marine gastropod mollusk in the family Buccinidae, the busycon whelks. 
•  Atlantic whelk shells are used for making seashell candles, as a seashell planter and perfect shells for airplants and their neutral color makes them a nice shell to display in a basket of shells.