I bought a kit with gasket, pre-filter and post-HEPA filter. My pad was in good condition so I don't really need it but probably need good insurance. However, the Dyson HEPA filter is a filter for life. Unless yours is damaged (open the vacuum and check) you don't need it. If you open a place where there is a HEPA filter, be careful. The Dyson's plastic becomes brittle and those three little protrusions break easily. Dirt can somehow get into the HEPA zone. A quick vacuum cleaner is useful, but there is most likely no new filter. Instead, I had to buy an extra pre-filter sponge that can dry while the other is under vacuum. This replacement part appears to be of good quality and fits the DC14 as expected.