Looks like one of attachment tools is missing, maybe the #10-32. See pictures for what is included

The Marson M39300 RN-1 Rivet Nut Setter is a high-quality hand tool designed for setting rivet nuts with sizes #8-32, #10-24, and #10-32. With a durable construction and precise design, this tool is perfect for automotive use and other applications where accurate rivet nut setting is required. The Marson brand ensures reliability and long-lasting performance, making it a valuable addition to any tool collection.