Manual Flexible Storage Systems allows the management of parts linking different steps of a production process, generating buffers between them while minimizing WIP (work-in-process). These systems are modular and designed with ergonomics in mind. Accessories include: stop stations, track switches to change lanes, transfer bars, and carts. Hangars are attached to roller trollies which travel on a mono-rail system minimizing handling by operators. These systems are typically designed as a closed loop process.