What is the trigger pack on the Colt 602 with the a1 rear sight type? 
CREATE TABLE table_19901_1 (trigger_pack VARCHAR, rear_sight_type VARCHAR, colt_model_no VARCHAR)
SELECT trigger_pack FROM table_19901_1 WHERE rear_sight_type = "A1" AND colt_model_no = "602"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_19901_1 (trigger_pack VARCHAR, rear_sight_type VARCHAR, colt_model_no VARCHAR) Question: What is the trigger pack on the Colt 602 with the a1 rear sight type?  [/INST] SELECT trigger_pack FROM table_19901_1 WHERE rear_sight_type = "A1" AND colt_model_no = "602" </s>