All but three of the 103 satellites scheduled to launch next month by the ISRO are foreign spacecraft, as India attempts this historic feat using but a single rocket.
The rocket in question is the PSLV-C37 and the date is set for February from the Satish Dhawan Space Center in Sriharikota. The ISRO had originally planned on an 83 satellite launch during the last week of January, of which 80 were foreign productions. However, as 20 additional foreign satellites were brought onboard, the launch date was pushed out until February during the first week of that month. According to S. Somnath, the Director of Liquid Propulsion Systems Center of the ISRO, there will be 100 of the foreign smallsats, with the total weight of the payload being 1,350 kgs, of which 500 to 600 kgs will be the weight of the satellites.
The largest number of satellites launch in a previous mission was Russia, and that was in 2014. NASA launched 29 simultaneously, and the ISRO last year launched 20 satellites in a single mission.