Bulk Small White Moon Shells for sale in a 1 kilo bag (2.2 pounds).  They measure between 3/4 inch and 1-1/4 inches in size.  Some may be a little under or over the size.  The second photo will show you what 2 pounds of shells looks like.

Naticidae, common name moon snails or necklace shells, is a family of medium to large-sized predatory sea snails, marine gastropod molluscs in the clade Littorinimorpha. The shells of the species in this family are mostly globular in shape. Naticidae is the only family in the superfamily Naticoidea.