When manufacturers send two different things that are the same.

One valve is for hot water and one is for cold - for a lavatory faucet.  I was obliged by the manufacturer to 

buy a new valve, hoping it would match the valve here with the most recent date (wouldn't you think?).  But guess what arrived?  A single valve that matched the older version.

That's not changing your specs.  That's being disorganized.