ERR2410 ERR2412 pistons

What's the difference between these two pistons?
ERR2410 is available from most parts places, but no ERR2412...

rumour has it that it might be an oversize piston - but thats just a guess.

I thought that at first, but I've found oversize pistons denoted as ERR2410010 ERR24010020 etc.

Galen said:

What's the difference between these two pistons?
ERR2410 is available from most parts places, but no ERR2412...

Click to expand...

They look the same and measure the same diameter but possibly the number denotes the supplier OR it could be an OEM number. I do know that the spark plugs at Austin Rover Longbridge used to have an OEM number and Joe Public only got these plugs when he bought a brand new car. The idea was that anyone found with these plugs in his ten year old banger would be right in the poo!