human
Considering the provided database schema and associated query, produce SQL code to retrieve the answer to the query. 
###Database Schema: Colt model no., Name, Stock, Fire control, Rear sight, Forward assist, Case deflector, Barrel length, Barrel profile, Barrel twist, Hand guards, Bayonet Lug, Muzzle device
###Question: What are the Colt model numbers of the models named GAU-5A/A, with no bayonet lug, no case deflector and stock of 2nd generation? 
gpt
SELECT Colt model no. FROM table WHERE Bayonet Lug = No AND Stock = 2nd Generation AND Case deflector = No AND Name = GAU-5A/A