This unit is identical to our Model 8 except that all the connections are made using individual pin jacks and 24 gauge, solid-wire jumpers. Any RS-232C wiring arrangement can be made without soldering and can be easily changed by simply re-arranging the jumpers. Our new snap-together/pop-open case encloses the wiring, and has enough height (.4") to allow all 25 jumpers to be used! We also give you pressure-sensitive labels where you can draw your wiring connections, plus a clear plastic cover to stick on top of them for protection.