Table:
text: AR-15 variants
LE series models
LE series models
Colt_model_no_ Name_ Stock Fire_control Rear_sight Forward_assist Barrel_length Barrel_profile Barrel_twist Hand_guards Bayonet_Lug Muzzle_device
LE1020 Gas Piston Carbine 4th Generation S-1 Flattop Yes 16 in. M4 1:7 Rail System Yes A2
LE1033 Gas Piston Commando 4th Generation S-1 Flattop Yes 11.5 in. A2 1:7 Rail System Yes A2
LE6920HB Law Enforcement Carbine 4th Generation S-1 Flattop Yes 16 in. M4 HBAR 1:7 M4 Yes A2
LE6921 M4LE Carbine 4th Generation S-1 Flattop Yes 14.5 in. M4 1:7 M4 Yes A2
LE6921CQB M4LE Carbine 4th Generation S-1 Flattop Yes 10.5 in. M4 HBAR 1:7 M4 Yes A2
LE6921HB M4LE Carbine 4th Generation S-1 Flattop Yes 14.5 in. M4 HBAR 1:7 M4 Yes A2

Question: What is the muzzle device on the LE series models, the Colt model le1020 among the AR-15 variants?

Question: What barrel profile fits the gas piston carbine among the LE series models of the AR-15 variants?

Question: What handguard system is used with a gas piston commando on the AR-15 variants of the LE series models?