As the regulars make up three quarters of the ISA forces, the Vektan regulars sustained the brunt of the Helghast invasion and suffered high casualty rates defending the planet. One of the regulars standard size units is a division, there is possibly one division per colony, or else it varies depending on funding available in that colony. Some Regulars who display strength, courage and duty more so than others, are given special training and become Heavy Weapons Experts - essentially 'Human Tanks'. They are given the heaviest portable weapons available such as the M224-A3 Chain Gun and M404 Missile Launchers and are used as human bulldozers to plough through enemy defences. ISA Regulars are at times called the life blood of the ISA ground forces.