I-4K is a satellite bus being developed by Indian Space Research Organisation (ISRO).^[1][2] It will be a standard bus for 4,000–6,500 kg (8,800–14,300 lb) class communication satellites;^[3] the I in I-4K stands for INSAT, a group of communication satellites developed and launched by ISRO. The I-4K spacecraft bus can supply DC power of 10 to 15 kilowatts.^[1][4]