CREATE TABLE table_72337 ("Colt model no." CLOB, "Name" CLOB, "Stock" CLOB, "Fire control" CLOB, "Rear sight" CLOB, "Forward assist" CLOB, "Case deflector" CLOB, "Barrel length" CLOB, "Barrel profile" CLOB, "Barrel twist" CLOB, "Hand guards" CLOB, "Bayonet Lug" CLOB, "Muzzle device" CLOB)

What's the type of muzzle devices on the models with round hand guards?
SELECT "Muzzle device" FROM table_72337 WHERE "Hand guards" = 'Round'
SELECT "Muzzle device" FROM "table_72337" WHERE "Hand guards" = 'Round'