Press introducing American backed no 1 sewing aid (10)

'sewing aid' is the definition.
(a pincushion may be used when sewing)

'press introducing american backed no 1' is the wordplay.
I cannot really understand how this works, but
'american' could be 'us' (abbreviation for United States) and 'us' is found within the answer.
'press' could be 'pinch' (pinch is a kind of press) and 'pinch' is located in the leftover letters.
'no' could be 'o' (O resembles 0) and 'o' is present in the answer.
'1' could be 'i' (roman numeral) and 'i' is found within the answer.
A single letter 'n' remains which might be clued in a way I don't understand.
This may be the basis of clue (or it may be nonsense).