Firmware_V5.5.821_231108 IPC E6 5.5.821 Release Note Applied to: DS-2CD2421G0-I(2.8mm) DS-2CD2421G0-I(2.0mm) DS-2CD2421G0-I(4mm) Firmware_V5.7.23_241008 Applied to: DS-2CD2421G0-I(2mm)(C) DS-2CD2421G0-I(2.8mm)(C) DS-2CD2421G0-I(4mm)(C) Hikvision.com uses stric...