Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_74300 ( "For shank type" text, "Singer part number" text, "Uses templates?" text, "Description" text, "Storage case" text )

### Question ###
What's the singer part number of the buttonholer whose storage case is a green plastic box?

### Accurate SQL ###

SELECT "Singer part number" FROM table_74300 WHERE "Storage case" = 'green plastic box'