The CHF-400 is a replaceable pressurized canister containing 400mL of dense hydraulic fluid, serving as the primary ammunition for hydrostatic weapons platforms that project focused columns of fluid at high velocity. The canister maintains internal pressure sufficient for 6-8 full-power discharges, with the weapon's electromagnetic shaping system forming the fluid into coherent streams, dispersed clouds, or focused jets depending on the engagement mode.

The hydraulic fluid itself is a synthetic compound engineered for specific density, viscosity, and electromagnetic responsiveness — properties that allow the weapon's field generators to manipulate the fluid with precision during projection. Standard CHF-400 fluid is biologically inert, designed purely for kinetic effect through hydrostatic pressure transfer. However, the canister format accepts modified fluid formulations, and the black market offers variants loaded with corrosive, conductive, or biologically active fluids that expand the weapon's capability well beyond its designed parameters.

The canister's pressurization system uses a captive gas charge that maintains consistent delivery pressure across the discharge cycle. As fluid is consumed, the gas charge expands to maintain pressure, ensuring that the first and last shots from a canister deliver equivalent performance. The canister is field-replaceable in approximately 4 seconds, with a mechanical interlock that prevents accidental disconnection during operation.