CREATE TABLE table_17831 ("Colt model no." CLOB, "Diemaco model" CLOB, "Stock" CLOB, "Fire control" CLOB, "Rear sight" CLOB, "Forward assist" CLOB, "Barrel length" CLOB, "Barrel profile" CLOB, "Barrel twist" CLOB, "Hand guards" CLOB, "Bayonet Lug" CLOB, "Muzzle device" CLOB)

What kind of hand guards are associated with a rear sight of A1 and stock of A2?
SELECT "Hand guards" FROM table_17831 WHERE "Rear sight" = 'A1' AND "Stock" = 'A2'
SELECT "Hand guards" FROM "table_17831" WHERE "Rear sight" = 'A1' AND "Stock" = 'A2'