Run a Scurion on non-rechargeable batteries.
The 9v adaptor allows any of the Speleo models to be run on the standard 9v battery (the small oblong one). This will fit into the standard Scurion battery box and therefore is as tough as if using the rechargeable Li-Ion batteries.
This allows the Scurion to be used in remote areas where recharging is not an option, or as a backup on long caving trips where the carrying of a full-specification spare Li-Ion is not required.
Note that the 9v battery will not allow the Scurion to run on its brightest settings, but has a good duration on the lower settings (24 hours on the lowest 700 setting). Also, remember that this adaptor is supplied as standard with the 700 model!