The innovative I-beam and webbing design allowed the parts to meet the 32–38 HRC hardness range requirement and still maintain the total weight of the kit below 100 g (3.5 oz.). Molded from MIM-17-4 PH stainless steel, the parts have >7.5 g/cm³ density, 900 MPa (130,000 psi) ultimate tensile strength, 730 MPa (106,000 psi) yield strength, and 6% elongation. The only secondary processing of these near-net shaped parts are a coining operation to the bracket in order to achieve the tolerance required for the distance between the notch and the through-hole, as well as tapping the hole to provide necessary threading. Both parts are black oxided to remove their reflective properties, a critical consideration for the safety of the soldier.
- Extended the service life of the weapon by enabling the soldier to repair it in the field, thus avoiding the cost to taxpayers of a new weapon, which can be as high as $3,200.
- MIM provided 100% conformity to these component elements and functional features in a high-production setting, whereas other processes such as casting and machining would not have been practical.
- Drop testing of the firearm with the device attached proved the integrity of the FSIK even while other components were damaged.
- Maintained a low overall weight.