With only 13 liters of fuel capacity from the factory, the BMW HP2 will most likely drain the stock tank before you're ready to be done riding.  This auxiliary underseat tank adds 7.1 liters of additional fuel capacity that can be pumped into the main tank to increase your range by over 50%.  

The tank is constructed of 6mm polyethylene and the newly updated design will fit both the Enduro and Megamoto models with either the stock Continental or aftermarket Ohlins, Wilbers, or WP shock.  The tank mounts with the original BMW passenger peg mounts (some DIY may be required) or using an aluminum mounting bar, available separately.  

An electric fuel pump to expedite filling the main tank from the auxiliary underseat tank is also available.