I need to get a new door seal for my Zanussi ZWF1021W 6kg(Pr N 914205103, Ser No 53600280) washing machine. After researching it on the internet, I’ve come across 2 possibilities. The part numbers are 1320041906 and 1321187013. What’s the difference between the two? Both claim to be compatible for my washing machine but I don’t want to buy the wrong one. Can anyone offer any advice?