user: Question: Which Back has a Supplier of Kooga and a Year of 2006-2008?
Columns: ['Year', 'Supplier', 'Chest', 'Sleeves', 'Back']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['unknown', 'Gilbert', 'unknown', 'unknown', 'unknown']
SQL:

assistant: SELECT "Back" FROM "Table" WHERE "Supplier" = 'Kooga' AND "Year" = '2006-2008';