Magellan GPS315

[Dutchmerc]

Hello,

Recently i have put my hands on a portibal GPS device, a Magellan GPS315. :) ;D It works just fine , but there is one big issue.  :oIt uses more power than a normal AA batery can provide.. I need at least 2 sets of 2 AA-bateries every trip. (I use the GPS on my boat.)
Now I am looking for a way to connect the device to my 12V battery. The device has 4 "pins"at the back, to connect to a cable. I did not get any cable with it, but if i find the layout from these pinns, i might be able to make myself a cable....
Who can tell me if and where i can connect the +12VDC and 0VDC cable? :-\ ???