I took apart a utility sink hot-water faucet over
the weekend to replace the washer, and discovered
that this faucet's stem uses a type of washer I've
never seen before: if you visualize laying it
flat, then "cutting" it from top to bottom, the
washer's cross-section isn't flat or beveled, but
rather shaped roughly like a crown. Has anyone
run into these? Does anyone still make them?