The first variation, the standard LARC was originally a modified C-Defender, hence the stylistic similarities, but featured a new cannon and different booster arrangement.
This craft is a variation of the standard LARC but with anti-gravity boosters replacing the original rockets and a Type-4 C-Defender cockpit. It is the only version still in production.
The second LARC variation. It is identical to the 1LARC except for it's extra cannon, which is located on the bottom of the craft.
The LARC-37 is a significantly lengthened LARC with 37 main cannons. It can split in two and was designed by DWC as a demonstrator, and not intended for production.