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_19901_1 ( muzzle_device VARCHAR, colt_model_no VARCHAR )

### Question ###
Which muzzle devices are on the Colt 603?

### Accurate SQL ###

SELECT muzzle_device FROM table_19901_1 WHERE colt_model_no = "603"