What is the mailing cost of posting a DVD within UK?

Standard 1st Class (no track): 86 pence (1 CD/DVD) OR £1.62 (2CD/DVDs)

Signed For® 1st Class: £2.65 (Any amount of CD/DVDs)

UK Second Class DVD Post (up to 100g / CD / DVD / up to 2cm height)*

Standard 2nd Class (no track): 51 pence (Any amount of CD/DVDs)

Signed For® 2nd Class (Any amount of CD/DVDs): £1.23