A fine pair of shells

Today's fresh air was back to the old favoutrite of Baleshare beach and we didn't get too wet. Great views of a female Peregrine terrorising most of the local birds up to and including the thousand Barnacle Geese there.
At the other end of the spectrum were these little shells - you can gauge their size from the grains of sand in the image - washed up by the strong tides. I am not quite sure what they are but think they are some kind of whelk. I will try and find out.