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_1637981_7 ( kalamazoo__azo_ VARCHAR, saginaw__mbs_ VARCHAR )

### Question ###
What is the fare to Kalamazoo during the time frame when Saginaw's was $481.39?

### Accurate SQL ###

SELECT kalamazoo__azo_ FROM table_1637981_7 WHERE saginaw__mbs_ = "$481.39"