for my 16" LMT upper that just came in the mail today:D I plan on putting a DD Lite 9" eventually but for now the regular handguards will do, until I get all of the important stuff, ammo, mags, spare bcg and other parts etc. some look bigger and rounder than others:confused: some descriptions even state they are the larger oval design. I’m a product of the M16A2 generation so this M4 stuff is new to me:o
CAR Handguards and FAT handguards are the same lengths, just different widths…
I thought I read somewhere awhile ago there were fitment issues with the two different styles:confused:
In your hands, maybe 
On all rifles, the delta ring and handguard cap are the same dimensions…only difference is the length, and the occasional A1 triangle handguard cap…
Yes, the length & width of each rail varies from maker to maker. Daniel Defense are REALLY tall an oval shaped, YHM are very round, LaRue & LMT (MRP) are both very slip and short, KAC is somewhere in the middle while still being more oval than round.
It’s all a matter of what suits you. If you have the opportunity, handle as many as you can to see what’s best for you.
good to know, I didn’t wanna spend $35 on LMT handguards vs. $20 for others or maybe even something cheaper on GB, I don’t need a double heat shield b/c I wear gloves when I shoot anyways.
Unless you are doing beta mag dumps with a full auto you really dont need a single heat shield…
Whoops! I thought you meant railed handguards…