A2 handguards are not free floated. These plastic handguards have metal heat shields to on the inside to protect the shooter from the heat generated by the barrel during intense firing of the weapon. The photo below shows a carbine length A2 handguard.

Magpul MOE handguards are similar to the A2 handguards in that they are plastic and not free floated, but the MOE handguards have the advantage that they are modular and accept accessories such as foregrips and weapon mounted lights and lasers.

Free float forearms are forearms in which the only point of contact between the rifle and the forearm is at the barrel nut. In this configuration, it is the barrel that is free floated, and as such nothing is touching or interfering with the barrel while shooting. With a free floated barrel, the rifle will achieve peak accuracy as the barrel will not be interfered with in any way while shooting. The interference that occurs with a non-free floated setup is slightly different with every shot, which will cause the point of impact of the rifle to change on every shot.
In order to take maximum advantage of a free float forearm, the weapon should not rest on the barrel when shooting. A forearm mounted bipod, or resting the forearm on sandbags etc. is the recommended approach when shooting.
Basic free float forearms feature no rails and limited or no attachment points for accessories such as bipods and sling swivels. Forearms include YHM free float, Hogue knurled or overmolded, White Oak varmint tube, and PRI carbon fiber target forearm. These forearms are simple, light, and provide maximum accuracy.
Mid length forearms are 9" long and leave the gas block exposed when used with a mid-gas barrel. Rifle length forearms require a low-profile gas block when used with a mid-gas barrel, and are typically 12" in length.

Yankee Hill Free Float Tube

White Oak Varmint Tube

Hogue Overmolded Forend

PRI Gen III Target Forearm
Modular free float forearms have less integral rail capacity than quad rail forearms. Some modular forearms have no rails at all, while others feature an integral top rail, and most allow attachment of short or full length rail sections. Picatinny rails serve as attachment points for accessories such as tactical lights, foregrips, bipods, and sling swivels. Forearms include YHM smooth and customizable series, Troy TRX Extreme, Midwest Industries SS-series, and Gen III carbon fiber forearms. These forearms are simple, light, and provide maximum accuracy.
Mid length forearms are 9" long and leave the gas block exposed when used with a mid-gas barrel. Rifle length forearms require a low-profile gas block when used with a mid-gas barrel, and are typically 12" in length. These field proven modular forearms are light weight, versatile, and some of the best offered in the country.

YHM Customizable forearm - carbine length

YHM Smooth forearm - rifle length

Midwest Industries SS series - mid length

Troy TRX Extreme 11" forearm

PRI Gen III forearm - rifle length
Quad rail free float forearms feature four full length Picatinny attachment points for accessories such as tactical lights, foregrips, bipods, and sling swivels. Forearms include YHM lightweight and diamond series, Troy TRX, Midwest Industries T-series, and Daniel Defense Lite rails. These forearms are simple, light, and provide maximum accuracy.
Mid length forearms are 9" long and leave the gas block exposed when used with a mid-gas barrel. Rifle length forearms require a low-profile gas block when used with a mid-gas barrel, and are typically 12" in length. These field proven quad rail forearms are some of the best offered in the country.

Yankee Hill lightweight quad rail - rifle length

Yankee Hill Diamond series quad rail - mid length

Troy TRX 13" quad rail forearm

Midwest Industries T series quad rail forearm - mid length

Daniel Defense Lite Rail forearm - mid length