CNS41
It is a type of screw used to connect two parts together. The "M4" refers to the size of the screw, with the "M" indicating it’s a metric screw and "4" meaning the diameter is 4 millimeters. The sleeve part of the screw is a tube-like component that fits over the screw, providing extra support and stability for the connection. It’s commonly used in furniture assembly, machinery, and other applications where a secure connection is needed.