You wouldn't buy a pack of small to large socks for you or your child and hope to get the ones that actually fit, only to be left with the rest. We realized from our purchasing experience that our customers hermit crabs can be quite selective when sizing up a shell for them to change into. Too many times we hermit crab owners do our shopping and spend over and over again on shell packs that are a 50/50 shot at being the size our aquatic pets need to be comfortable with as the hermit crabs grow. Most online options offer hermit crab shells by size ranges with little more assurance as to what specific sizes will be provided. Based on that pain in the buying experience, we rolled out our shell up-sizing packages to better serve the needs of the customers. We collect and clean shells from the beach, and then measure them with precision to offer three one sixteenth of an inch size increments based on the current shell size of the hermit crab in need.