Performed a full recharge of an ABC dry chemical fire extinguisher. First, I depressurized the unit and disassembled it for inspection. The cylinder was cleaned, and I replaced the internal O-ring to ensure a proper seal. After refilling the unit with the correct amount of dry chemical agent, I reassembled it and pressurized it to the required 195 psi using a regulated nitrogen source. I then inspected the hose and nozzle for any blockages and reattached them. Finally, I tagged the extinguisher with updated service information and confirmed it was ready for use.