DS-2DE3A400BW-DE(T5) is an improved version of DS-2DE3A400BW-DE(F1)(S5) with various improvements.
Read much more about it - and everything else - on the product page for the new version: DS-2DE3A400BW-DE(T5)
We have kept the product page for DS-2DE3A400BW-DE(F1)(S5) so that you always have easy access to the documentation.