I'm included in transfer of ten (7)
I believe the answer is:
decimal
'of ten' is the definition.
(I've seen this in another clue)
'i'm included in transfer' is the wordplay.
'included in' indicates putting letters inside.
'transfer' becomes 'decal' (design transferred onto a surface).
'im' inserted inside 'decal' is 'DECIMAL'.
(Other definitions for decimal that I've seen before include "Based on the number 10" , "fraction" , "Relating to ten" , "of Number Ten" , "Claimed, wrongly, to have this currency" .)