Rarely see these guys at Pillar Point - this one was huge!
As a child visiting Monterey county we collected shells; alas this wonderful segmented mollusk was not collectible unless you copped the entire creature, and of course hid the smelly corpse from Mother until it yielded it's imperishable segments.
We'd the same issue with our several expired turtles...
Chitons (sg. pronounced /ˈkaɪtən/) are small to large, primitive marine molluscs in the class Polyplacophora. There are 900 to 1,000 extant species of chitons in the class, which was formerly known as Amphineura.