Abstract: What is disclosed is a versatile interlocking crossbar device and system for coupling modular components of toy assemblages, educational models, hobby constructions, component attachments, or the like together using one or more connectors, configured with a set of male connector parts and a set of female connector parts, configured to enable the selective attachment of such parts. The disclosed system is exemplified in this application as a toy vehicle and a ball and demonstrates how the parts and interlocking crossbar device interrelate to one another in a plurality of ways to create varying embodiments. The unique interrelationships spoken of are, for the most part, capable of creation because similar sized openings and recesses are indexed within each body member such that the pieces and interlocking crossbar conform thereto.