CREATE TABLE table_66917 ("Colt model no." TEXT, "Name" TEXT, "Stock" TEXT, "Fire control" TEXT, "Rear sight" TEXT, "Forward assist" TEXT, "Case deflector" TEXT, "Barrel length" TEXT, "Barrel profile" TEXT, "Barrel twist" TEXT, "Hand guards" TEXT, "Bayonet Lug" TEXT, "Muzzle device" TEXT)

Name the bayonet lug with ar-15 lightweight
SELECT "Bayonet Lug" FROM table_66917 WHERE "Name" = 'ar-15 lightweight'
SELECT "Bayonet Lug" FROM "table_66917" WHERE "Name" = 'ar-15 lightweight'