Great look, fit and function...and one myth! - Command Arms M4S1 Handguard & Rail System for AR15/M16 Carbines

Nothing that looks this good is available for ARs with delta ring hand guards. It is virtually impervious to heat (but doesn't have metal heat shields). I have two lightweight builds that wear them. The whole assembly weighs less than half a pound. It feels great in your hand.
But there is no optional aluminum top rail that runs the length to the upper receiver. CAA does offer the TRM3 polymer rail cover, but that is for a conventional M4 hand guard. It will resemble the M4s1, but it doesn't fit on one.
The aluminum rail? It doesn't exist!
Check their web site, call Customer Service. No such thing!