T91/Wolf A1 Handguards - Original, BB, Prototype?

T91 clones and Wolf A1 uppers have had very limited purpose built handguards. Here I go through a few of them

1. Original Handguard
2. Original Handguard with mods (tri rail)
3. Mlok Airsoft handguard
4. G&G mlok Airsoft handguard(incompatible with real firearms)
5. Quadrail airsoft handguard
6. BiaoTac Concept lower handguard