Table: ar15_variants_2
Columns: 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: Name the barrel length for rear sight a2 for factory compensator
SQL: SELECT "barrel_length" FROM ar15_variants_2 WHERE "rear_sight" = 'A2' AND "muzzle_device" = 'Factory compensator'

Question: Name the barrel twist for colt model mt6400
SQL: SELECT "barrel_twist" FROM ar15_variants_2 WHERE "colt_model_no" = 'MT6400'

Question: Name the forward assist for a2 barrel profile
SQL: SELECT "forward_assist" FROM ar15_variants_2 WHERE "barrel_profile" = 'A2'

Question: Name the stock for colt model mt6601
SQL: SELECT "stock" FROM ar15_variants_2 WHERE "colt_model_no" = 'MT6601'