Table:
text: AR-15 variants
AR series models
AR series models
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
AR6320 AR-15 Lightweight 4th Generation S-1 A1 Yes Yes 16 in. A1 1:9 Short Ribbed Yes A2
AR6450 AR-15 9mm Carbine 4th Generation S-1 A1 No Removable 16 in. A1 1:10 Short Ribbed Yes A1
AR6520 AR-15A2 Government Carbine 4th Generation S-1 A2 Yes Yes 16 in. A1 1:7 Short Ribbed Yes A2
AR6520SP AR-15A2 Government Carbine 4th Generation S-1 A2 Yes Yes 10 in. A2 1:7 Short Ribbed Yes A2
AR6525 AR-15A2 Government Carbine 4th Generation S-1 A2 Yes Yes 16 in. A2 1:9 Short Ribbed Yes A2

Question: Name the muzzle device with a barrel twist of 1:10 among the AR production models of the AR-15 variants?

Question: Name AR-15 lightweight bayonet mount among AR-15 variants among AR series models?

Question: Give the barrel length for AR 15 variants under the 1:7 barrel twist of the AR series models?