Airsoft Artisan MLOK Vertical Foregrip - VFG (Type A)
 
If you want a sleek lookin' polymer VFG for your CQB BB blaster build, Airsoft Artisan made a pretty dope one.
 
This is the Type A VFG, which is slightly more flared where it sits on the handguard, giving a better form factor when gripping the VFG.