Small container designed for ash etc. (6)
I believe the answer is:
sachet
'small container' is the definition.
(I've seen this before)
'designed for ash etc' is the wordplay.
'designed for' indicates an anagram (letters re-designed).
'ash'+'etc'='ashetc'
'ashetc' is an anagram of 'SACHET'.
(Other definitions for sachet that I've seen before include "Small packet (of, eg, shampoo)" , "Small envelope-like container" , "Small bag with sweet-smelling substance" , "Small bag or packet" , "Scent bag - shampoo envelope" .)