R.I.S , R.A.S difference?
 

fast question to ask ..... what is the difference between R.I.S , R.A.S?

sorry if its a stupid question

ras is free floating...ris attached behind the front sight. the delta threads on to the ras guards where the ris ones pop in....quick version of an answer

what about the daniel defense RIS 2. I know RIS is in its name but isnt it free floating similar to a RAS?

Directly from quarterbore
The RAS system clamps to the handguard cap via a clip on the top half while the rear is attached by a clamping mechanism that fits over the M-16 gas tube and fits into a recess in the M-16’s barrel nut. This rear clamp is then tightened via a hex-head screw producing a very tight fit that prevents most movement as experienced in RIS units.

The KAC RAS is NOT free floating , it clamps onto the gasblock ring and the barrel nut whereas the RIS only clamps onto the gasblock ring.
The KAC Free float RAS , free floats. Meaning that it attaches to the barrel nut and which holds the barrel in place but touches no other part of the barrel , increasing the stability of the barrel when more accessories are added to the rails.